Theory:Doctor Who television discontinuity and plot holes/Blink

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This page is for discussing the ways in which Blink doesn't fit well with other DWU narratives. You can also talk about the plot holes that render its own, internal narrative confusing.

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... and so on. 
  • I am currently in the middle of a later episode (no spoilers) where they mention paradoxes. Person A has killed Person B so they want to kill an earlier version of Person A so that he will never go on to kill Person B. But that won't work because the only reason they had the notion to stop Person A was because Person B was killed. So, in this episode the only reason the doctor has the conversation notes is because Sally transcribes the conversation notes because she has already had the conversation and can give it to the doctor who then goes back in time and reads the transcription. See the problem there? That means that the conversation itself materialised out of thin air. Nobody had an original thought. The only reason either of them said anything is because they knew what the other person said/was going to say. If that is not a paradox then I don't know what is.
Yes, this is a classic example of an ontological paradox (something exists whose ultimate cause is itself). But not all paradoxes affect the Whoniverse the same way. Some kinds of paradoxes are no problem at all, some are only a problem if they're observed, some are always a problem; some undo themselves automatically unless you provide energy to sustain them, some cause unstable alternate timelines to pop into being, some rip homes in spacetime, and some destroy the universe; some can be accomplished with no effort, some are difficult, and some are impossible. The details of all those distinctions aren't perfectly clear (or even consistent), especially if you only stick to the TV episodes, but the fact that there _are_ differences definitely is. And it's been pretty well established that ontological paradoxes, especially those only involving information, are easy to create and cause no problems.
One wonders why the Doctor wasn't able to bring Billy back to his own time via the TARDIS, but was still free to move after being sent back by the same Angels. If there's some kind of potential that they consume permanently, this hasn't been a problem for the Doctor. This makes sense, considering he doesn't age, but what about Martha? She's a human who got sent back, but she somehow gets a free pass for just being with the Doctor. Perhaps it's some effect of exposure to the Time Vortex? If you really wanted to stretch things, you could imagine the ontological paradox as the result of the displacement of the Vortex's energy snapping back to its proper place (seeing as the Angels apparently use other means of transport). Just a thought.
Well, time is wibbly-wobbly. I think that time gives you a "get out of paradox free" card if you don't make it physically impossible for you to have gone back. For example, if Person B didn't get killed, Person C (the time traveller mentioned in the original thing) still could've imagined Person A killing Person B, and so then they would've still gone back in time. However, if Person A is the time traveller, and they go back and kill themselves, then it rips a hole in time and space, because it would be physically impossible for them to have gone back.
Someone mentioned below that maybe he was only looking at her responses and responding ad lib, thus creating the words themselves and avoiding a complete paradox.
The key difference is between a paradox that is self-sustaining and one that is self-destructive.
By the way, the original thought was Sally's - she was saying what she wanted to say, asking what she wanted to know, because she didn't have any parts of the dialogue (Larry had the Doctor's part, but she didn't read it). This can be considered as a free will (which is questioned in such cases). No, she didn't know what the Doctor was about to say, because she'd never seen the full recording before. The Doctor did know, so yes, the rest part of it is a paradox, but it's not destructive, sometimes it's just the way Whoniverse works and it's entirely possible if time travel is involved. Which is never involved in real life, so it's hard for us to grasp the idea.
  • Sally sees the Weeping Angels on the edge of the building across the one she is in. She blinks, and they have moved to the edge of the building she is in now. There a lots of cars and people around, surely one of them would have seen?
No-one had any reason to look at the Angels, since they would have better things to do than to look at 'statues' for extended periods of time. Hardly anyone on a high street ever looks up into the sky.
What he/she means is while its travelling across the street someone would have seen and frozen it on the way across.
Assuming that it ran across the street rather than flying or jumping, that it didn't move too fast for anyone to notice, etc. Presumably one of those assumptions was wrong.
  • If the Angels can jump across a street, why did they not get Sally while she was tearing the wrapping up?
The Angels may not have jumped, they may be able to use their wings. Thus, it may not have been able to jump at Sally and could not fly at her without hitting the ceiling. Also the Angel could not have jumped right at Sally while she was peeling off the wallpaper as there was some walling present with a window through which the Angel could be seen and a door through which the Angel later came. If it jumped it may not have hit her and may instead have miscalculated the angle or hit a wall. Also, as stated in the video commentary, it was disadvantageous for the Angel to incapacitate Sally while she was concentrating on the wallpaper, since if she suddenly turned around it would have been caught.
  • How does the Weeping Angel get hold of the TARDIS key? If from the Doctor, why did they not use the key to get into the TARDIS straight away, having zapped him and Martha to 1969? After all, DI Shipton tells Sally Sparrow that the TARDIS was also found outside Wester Drumlins.
Even though the Weeping Angels found the key, they may not have found the TARDIS. The Doctor does have a habit of hiding the TARDIS in obscure or inconspicuous locations just in case.
The Doctor and Martha could have been running away from the Angels. If he took out the key so he could get into the TARDIS, he may have dropped it on the way. Once the Angels discovered that he had a TARDIS, they may have had to go back and search for the key.
It is possible that by the time the Angels had retrieved the key, the TARDIS had already been taken away. Given the number of vehicles that have been found at the house, this implies that the police might check there reasonably frequently. They only locate the TARDIS after following Sally, who stole the key.
It is much more likely that the Angels simply couldn't overcome the perception filter or didn't know what the TARDIS looked like until Sally led them to it.
  • In theory, the Angels would be able to escape when the light bulb eventually goes out, although the light stops flickering as soon as the TARDIS departs.
It is implied in that very scene that the Angels can see perfectly well in the dark.
If the Angels could see in the dark, then they couldn't move in the dark because they could see each other.
Yes, if they all end up facing each other so all of them are locked, then they can't move. That's what happens at the end. But in normal circumstances, they don't do that. They've been doing this for a very long time, so presumably they have some kind of system. For example, maybe they intentionally waste a tiny fraction of each second deliberately looking at each other (in a synchronized sequence so no two Angels are ever looking at the same time), just to spot and fix problems (oops, A looked early for some reason, so he and B are looking at each other, so I'll turn them). The only way that could possibly fail is if someone somehow tricked the whole group into looking at each other all at the same time (as the Doctor did).
Or they can't see in the dark, and they are just very aware of their surroundings.
  • How does the Doctor know exactly when Sally should duck?
The Doctor didn't know when Sally Sparrow should duck, he just did as the notes Sally gave him indicated.
  • Who threw the rock?
The Angel did. As mentioned in the audio commentary for the episode, it is advantageous for an Angel to incapacitate its victims by throwing something at them as it could then move freely.
  • When Sally pulls the last scrap of wallpaper off, the words are still slightly covered up. However, when the camera next points at them, they are completely uncovered.
She was in the process of uncovering them. The second between camera shots was quite enough time for her to pull more wallpaper away.
  • Sometimes they look away from the Angels many times but they don't move.
In an old house there are bound to be spiders, mice and rats and especially in the garden.
Until the end, they often had no urgency in sending their victims back.
When Sally took the key, it was actually in their interest not to send her back so they could use her to find the TARDIS.
  • At the start of the episode when the Angel knew she was there, why didn't the Angel get Sally while she was looking at the message?
It threw the rock at her, presumably to disable her so it could attack. Unfortunately for the Angel, it missed when she ducked.
  • Why wasn't the rock-throwing method ever repeated by the Angel? Say, with Kathy.
The Angel had the opportunity to get Kathy without throwing a rock, so a rock wasn't necessary. Hitting Kathy with a rock might have caused sufficient noise or commotion to draw Sally's attention. Earlier. when Sally's alone, throwing a rock is a good move because there would be nobody else around to see when the rock connected (had it actually done so).
  • Sally and Kathy have clearly been close friends for some time - close enough for Sally to have a key to Kathy's flat. Yet Sally's never met Kathy's brother, even though he lives with his sister?
The episode never really delves deeply into the Nightingales' back story. Many people become close friends without meeting each others' siblings.
  • The second shot of the Angel in its screaming face is different than the first shot because the Angel's arms have clearly taken a different position.
That's the point. When not being watched, they can move.
But it was, Sally and Larry were both looking at it.
The Weeping Angel was facing down at them at the laptop, but it changed when they jumped up.
  • How did the Doctor know Larry would be to Sally's left?
Because of the transcripts that Larry wrote out were sent back in time so the Doctor would read them.
  • The Doctor appears to be familiar with the early parts of Sally and Larry's discussion about the recording, even though Larry doesn't immediately start taking notes.
The Doctor's side of the conversation was already written down, so it doesn't matter whether the other side was available or not.
Larry does shorthand, which is an extremely fast way of taking accurate notes. It's entirely possible he could have "caught up". His multi-year obsession with the "egg forum" would have helped him focus his concentration in order to do so.
  • The recording of the Doctor talking to Sally was scripted word for word, but when Martha interrupts him to tell Sally that she's also stuck the Doctor looked quite surprised at the interruption.
The interruption either wasn't part of the transcript, or Martha's interruption and the Doctor's surprised look were both part of the act.
I'm guessing that the doctor is only looking at sally's part of the conversation to make it seem like more of a, well, conversation so the impulsiveness of a conversation would still be present, and also otherwise the words would have come from nowhere.
  • When the Weeping Angel reveals itself and Larry turns his back briefly to see it move up to him, he looks into the Angel's eyes. So why doesn't he become infected like in flesh and stone?
Either it's an ability that a Weeping Angel can choose to activate, or he didn't acually look into the eyes, and it was just for dramatic effect. That's probably what Moffat would say if he was asked that.
In The Time of Angels, the Doctor says that the Angels he had met before were 'scavengers' and were 'barely surviving'. This implies that they did not have sufficient power to be able to infect Larry.
Also, in Touched by an Angel, the Weeping Angels a variety from the normal Angels in that they feed on paradoxes. It is highly probable that the Angels feature in Blink were ones that were 'born' without the powers the Angels had in TTOA/FAS.
  • Why didn't Sally and Larry simply keep one eye open thus allowing them to keep an eye on the Angels whilst at the same time giving them the opportunity to rest the closed eye and switch eyes when needed?
They are clearly scared, and the thought of using one eye at a time probably wouldn't have occurred to them. It's also more physically challenging than it sounds, given the automatic aspect of blinking.
I can vouch, it's extremely hard, I've tried. In the end, it just doesn't clean your eyes enough.
Interestingly, this is the first thing Amy tries. Because she's amazingly clever, or because Moffat hadn't thought of that a few years ago but has since then, or because some fan asked him in the intervening time. From observing Amy, you can see how difficult it is.
Blinking doesn't work that way. Even if one of your eyes have recently been closed, you still get that instinct, that itch, to blink them both.
Try it out, you can alternate eyes for a pretty long time without blinking. It's difficult, and eventually you will fail (exactly as we saw with Amy), but it does at least give you more time between blinks.
I tried, and I only lasted about half a minute.
I'm sure you could last longer if your life depended on it.
  • With DI Billy Shipton zapped back to 1969 and dying in 2007, wouldn't it have been possible for his older and younger versions to run into each other between 1969 and 2007?
The chance of them actually meeting each other is really slim, and if they met his younger version wouldn't necessarily recognise his older self.
Of course they don't have to worry about meeting between 1969 and 2007, but Billy's year of birth — most likely in the 1980s or early 1990s — and 2007. It would have been quite easy for the "old" Billy to have avoided his younger self, because he already knew what "young Billy" had done and where his younger self had gone. Don't forget, too, that Shipton has a Caribbean accent, meaning that the possible years in which they could have met are even fewer as young Billy isn't in London for very much of his life.
  • When the transcript is shown there is no indication of how long Sally speaks for, so the Doctor would have no idea how many seconds he should wait before speaking again.
The Doctor is a super genius. He heard Sally talking briefly when she gave him the information, and using his incredible mathematical skills he worked out how fast she would talk in certain circumstances and with a bit of luck got it spot on.
Most experienced TV script editors can read a line and instinctively know how long it will take to say, despite having no idea how they do it consciously (just like catching a flying baseball, despite having no idea how to work out the parabolic trajectory), so why couldn't the Doctor do the same thing?
  • Why does Kathy contact Sally only after her disappearance, rather than sending the message sooner to try to prevent the disappearance? The Doctor warns Billy not to contact Sally at the wrong time, but how does Kathy know?
Kathy needed someone to deliver the message. For the messenger to be younger than 75 by the time of Kathy's disappearance but older than 10 when the message was issued, Kathy would have to wait at least until 1942 to send the message. By this time she was happily married with children in her new era, and wouldn't have wanted to undo that.
Besides, it would cause a paradox. Don't ask me why that would cause a paradox but not the thing with the transcript; time is wibbly-wobbly.
Kathy no doubt realised that giving Sally the message before might have prevented her happy marriage.
  • If Sally has several months - possibly a year - to put her notes together, why does the Doctor act like he is missing big parts of the story, such as what happens after Larry stops writing the transcript?
The Doctor saying those things were themselves part of the transcript. Even if Sally did include all the possible information she could, the Doctor couldn't change what he had to say because any changes he makes to the events Sally wrote about and gave to him would alter the outcome and possibly result in him and Martha both remaining trapped in the past as well as risking Sally and Larry's lives.
  • The Doctor says that the Weeping Angels become stone whenever they are observed by ANY living thing. This would include other living things like wild mammals and, more importantly, insects. The chance that the Angels would not be observed by ANY living thing, especially when outside within the view of a countless number of insects, with the possible exception of the basement scene, is incredibly slim. This could be used to explain those times that no one, save the audience, is looking at Angels, yet they are turned to stone.
Nearly all insects do not 'see' in the same manner we do. Many have light-sensory organs, but nothing that suggests they could accurately detect a lifeform which does not, as far as we know, emit infra-red radiation. Also, there are no other animals visible in the areas where the Angels are seen so it could be argued that there weren't any anyway.
A perhaps simpler explanation is that the Doctor is simplifying a tad. It might not be that any living creature can stop the Angels with a gaze, but any sentient living creature.
I think you mean "sapient" here, because things like wild animals are sentient.
More importantly, I think at least wild animals, if not insects, probably do count, in order to explain some of the other times the Angels couldn't move.
Since even physicists who believe in the "active" version of the Copenhagen Interpretation of quantum physics (observation causes collapse of the waveform) can't come up with a good definition of what counts as an "observation", I don't think you can fault Moffat too much for not solving an 80-year-old problem in a TV script.
  • How would catching and touching Sally have helped the Angels at all? It would have sent her back in time with the key where they couldn't have gotten the key and therefore the TARDIS.
The Angels can move faster than a person can blink, this means they could easily catch up to Sally, remove the key from her and send her back in time without ever being seen.
It is also possible that since the Angels are described as a race of assassins, that their time travel ability is something separate to their natural Quantum-locking ability, much like a knife or gun is not a natural part of a human.
The Angels are seen to kill people physically, without sending them back to the past, in TV: The Time of Angels and TV: Flesh and Stone.
  • The Doctor said that the Angels are faster than you can believe and could kill you in the blink of an eye. So how was Larry able to get to the cellar without the Angel catching up to him?
As the Doctor said, they turn to stone when any living thing sees them, and its likely that a old, abandoned, condemned house has a few living creatures in it. Either that or the Angels just find it fun to scare their prey, and see no reason to hurry.
Well the Angel probably can only see the last thing it saw when it freezes, so from the Angel's point of view, - Larry was there one second and then gone next, so it was probably trying to figure out where he went.
It's equally possible they were deliberately herding the couple to the basement for an easier "kill", or that they didn't want to risk zapping Sally to the past with the TARDIS key in her hand.
Perhaps they wanted to ensure that the door to the TARDIS was opened before zapping.
  • Why couldn't the Doctor get a job? His mental and physical abilities are beyond that of humans, so it doesn't make sense that he couldn't get one, especially as he is a Doctor, a job that at the time, and to this day, is very much in demand.
The thought of having a regular job has been shown to unnerve the Doctor in the past, so since he already had the notes from Sally and so a means to get the TARDIS back he must have decided to focus on that. Also it would attract suspicion if people found out exactly how smart the Doctor really was.
In most of the novels where the Doctor and his companions stick around somewhere long enough to get a job, the companions succeed just fine, and the Doctor ends up in trouble (often in jail).
Makes you wonder how did his granddaughter affords school fee if he wouldn't get a job back in An Unearthly Child.
  • You can't get that much money working in a shop, yet when you see them and the Doctor and Martha meet up with Billy, they look immaculate.
The pay you get from working in a shop would be enough to get by on, and to keep your clothes clean. Lots of people work in shops and can pay mortgages and raise children.
It is implied that Billy films the video. Therefore, they would have met Billy before the video was made and possibly before Martha got a job.
  • It is highly likely that the Easter egg was filmed in 1969 but there were no DVDs in 1969 and video publishing was probably not widely used either.
The Doctor was able to manufacture a Betamax tape recorder during the Queens coronation ceremony - 50 years before the real technology was developed, using nothing but spare parts in an electronics store. He could then have given it to Billy Shipton would could then have transferred the data onto the 17 DVDs.
If it weren't possible to transfer old films to DVDs, we wouldn't have any DVDs of old films.
Also, if the Doctor could manufacture a Betamax 50 years ahead of time, he could have manufactured a DVD recorder a few decades early.
Not that it makes any difference, but it's only about 25 years, not 50.
  • When the Doctor reads the transcript, Sally turns around and sees the shadow of three Weeping Angels moving. But if she is observing part of them they shouldn't be moving.
The Angels are only affected by being directly observed, as described by the Doctor. Observing their shadow is merely seeing the obstruction of light as they pass across a light source and is not a tangible part of the actual creature, so they are unaffected.
  • When Larry turns around when he's staring at the Angel, he turns back again and the Angel is right in front of him but in the next shot it is about 6 inches away and its hands are pointing at him.
This is a borderline production error, but there's nothing about the way the scene is cut that suggests he couldn't have moved back.
  • When Sally takes the key in the attic and looks at it, a shadow is seen coming towards her on her hair.
It is the Angel she took the key from.
  • Why didn't the photo Sally took of the Angels and gave to the Doctor become an Angel, just like the recording did in Flesh and Stone?
They were scavengers, not up to full strength, so may not have had this power to turn a picture of them into an Angel. Also when they come out of recordings they are just projections of the real thing, but since all of them are eternally made of stone they couldn't project themselves.
Also, they might only have that ability with video.
Also also, they might only have that ability if it's the full image; part of the angel was cut off at the bottom.
This also may be how the Angels that got the Doctor and Martha came into existence in the first place.
  • Why didn't Martha and the Doctor take Billy with them when they came back to the present day?
Because that would create a paradox, as it was Billy who told Sally a hint that meant that they got the TARDIS back, if he never told her, how would they get the TARDIS?
And that kind of paradox: 'an action removing the reason for that action', is generally more bad in the Whoniverse than other kinds.
  • Why doesn't Larry make sense of the situation sooner? The easter egg made no sense to us when we first saw it because we only saw random snippets, but if you listen to the whole thing as Larry and his internet buddies have you would clearly have made sense of it, as the Doctor clearly explains that he's a time traveller stuck in the past, and then proceeds to give a very thorough description of the angels.
Because if you are told by someone that he has travelled in time you wouldn't believe and so with the other things the Doctor said.
  • When Billy arrived in 1969, he was met by the Doctor and Martha. In 2007, Billy is an old man, but Martha does not age at all during this time.
Billy was sent back to 1969 and lived his life through to 2007, ageing. Martha was sent back to 1969, but returned to 2007 via the TARDIS when it was sent back to 1969 by Sally and Larry.
  • Since Billy was a policeman when he was sent back to 1969 (lucky he was sent to the same time & place as the Doctor & Martha and not to 1920, hmmm?), neither he, nor the Doctor nor Martha had any resources, no money, no equipment (aside from the screwdriver), no TARDIS. So, how why would the Doctor just happen to be carrying the transcripts with him when the Angel zapped him to the past and how did the three of them have the wherewithal to film the conversations that would eventually be put on DVDs? I mean, which part of the transcript came first, Sally's or the Doctor's? It couldn't have been the Doctor's because he was reading from the transcripts he got from Sally. But Sally was responding to what she heard and saw the Doctor say, so her part must have come after his. Causality is so often circular in DW with A causing B and B causing A with nothing ever identified as the original action that began the chain of events.
The doctor carries a lot of random things in his coat so maybe it's just bigger on the inside like the TARDIS, or maybe something in the transcripts let him know when he should have it on him. Maybe when he realized he was parking the TARDIS near that house he grabbed the papers just in case he would need them. Also the transcript was complete at the time he received it, Larry had written in both sides of the conversation and the Doctor just had to read it like a script. In that way it is a paradox but an apparently harmless one. Also someone said above that the Doctor may have only been reading and responding to Sally's parts to make the conversation more real and of course got his own responses word for word (as they were his own). As for wherewithal, the Doctor has been shown to use his sonic screwdriver to get money before. Maybe he only does that in emergencies or when he doesn't expect to stay long. Maybe he did that until they could get on their feet (it is kind of cheaty isn't it) which is when Martha gets a job and Billy works at the recording company to help the Doctor and Sally. Also the Doctor is crafty, we've seen him make devices way ahead of their time using stuff he's scrounged up from junk piles.
It's actually mentioned quite often that his pockets are bigger on the inside. He probably kept it in an inner pocket to have handy when the time came, since he knew he'd get stuck without the TARDIS. Also, knowing he'd get stuck there in the future, he may have purchased some necessities. He's smart enough, and resourceful enough.
(1) The Doctor specifically mentions that Billy was zapped by the same Angel that attacked Martha and him. (2) When Sally gave the Doctor her notes, she advised him to keep them on his person at all times. And no doubt after taking an initial look he would have concurred. (3) As mentioned earlier, the Doctor is extremely resourceful - especially if he has some advance warning.
  • After The Doctor says that Sally needs to get the blue box back he says there is no more to the transcript but she had responded "How? How?" Larry was watching an angel at the time but wouldn't he have written that in later, being so obsessed with completing the transcripts? Also did Larry write his own responses in? Because every now and then the Doctor responded to things he had said but Larry never mentions writing what he says down.
I can't read shorthand, but I'd guess that Larry wrote everything, since he was noting the way it flowed as a conversation. They may have left off the end of the conversation purposely, or maybe the Doctor had a lemonade in his pocket and it spilled. We all know how fond he is of Lemonade.
If Larry did finish the transcript the Doctor would have still said that the transcript was finished as he had to say his line even if it wasn't true because if he said something else he could have changed how Sally and Larry acted which could easily have caused a paradox.
  • When Sally is taking the key from the Angel, the Angel behind her covers its face; while the Angel by the window is looking in its direction. The Angel by the window then covers its eyes but the one that was behind her already had moved.
  • How come when the Doctor and Martha are back in 1969 and the TARDIS is still in 2007, the Doctor (and potentially Martha) is/are not around in 2007 since the TARDIS has not gone back in time yet? Wouldn't the 1969 timeflow keep going until the TARDIS is sent back to change time again? Or is that too much timey wimey?
The Doctor and Martha are in 1969 even though the TARDIS is in 2007, because they didn't go back in time via the TARDIS. They were touched by an Angel.
  • What I never understood is why he couldn't have just waited it out. The Doctor is immortal, he could have gotten to the TARDIS just as his other self is teleported to the past. Then he could go back and fetch Martha.
The Doctor isn't immortal; he just ages a lot slower than humans do as shown in a later episode (sorry I can't say the name, no spoilers). But the Doctor could have just waited like you say; but he can't bare the thought of waiting for decades so he decides to talk to Sally instead.
Besides, that would mean risking that Martha would be bound to live her whole life in the past, which she clearly wasn't really happy about. Even if he sent her away somewhere so he didn't know where she is and what happens to her, there was still a risk he wouldn't come back and find her in time (which is a precedent). And above all else he never even had to choose - he had the transcript and knew exactly what happened, all that was left for him to do was to follow the instructions - meet Billy, record the video etc, there was no other way, as any other way would change history and create a paradox.
It’s obviously infeasible for production reasons, but nothing explicitly would have prevented the Doctor, when trapped in 1969, from waiting a few months, then travelling to Ashbridge Cottage Hospital to borrow his own TARDIS from the place and time it landed in Spearhead From Space. In principle, he and Martha could then have returned to 2007 without difficulty. (The precise length of his wait depending upon UNIT chronology, of course.)
  • In PROSE: Touched by an Angel, it is revealed that people touched by Angels are sent to the same coordinates as where they came from. Yet in this episode, Kathy is sent from the middle of London to Hull.
In The Angels Take Manhattan (TV story) a similar thing happens to Rory which suggests that angels usually send people to the same place but don't have to (I hope this helps but I haven't seen Touched by an Angel so I'm sorry if this is contradicted.)
This discontinuity should rather be noted on the later story, not here.
  • How is it that Martha and the Doctor were able to travel multiple times to the same year to watch the Moon launch? How did that not constitute crossing ones own timeline?
They most likely viewed the launch from different angles so as to avoid crossing their own timeline. Their future selves would know where they watched the landing in the past and could work around it.
  • How the TARDIS has the Security Protocol 712, since the Doctor and Martha were trapped in 1969?
  • Why did the Doctor go to the trouble of making the video and all the Easter Egg DVDs, warn Sally about the Angels and tell her that she needed to get the TARDIS to him, but then not tell her how to do that? Why would he take the chance that she would figure it out for herself? There's no reason his trail of thought should have derailed just because her side of the transcript ended.
The transcript ending indicates that something bad is about to happen to Sally. The Doctor's priority was telling her how to avoid the Angels. There wasn't enough time to tell her how the TARDIS works.
  • In Logopolis, the police are able to open the TARDIS using a regular police box master key, but see only a cupboard. However now, no key works on the police box, and it's considered a fake prop?
Upgrade? Time has passed, the Doctor could've decided it's safer not to let anyone open the TARDIS at all than let them see a fake interior. Just in case this inner chameleon system fails someday.
  • The angels travel very fast and as soon as they are observed they turn to stone. Why do they suddenly stop when they are observed? Shouldn't their high momentum cause them to keep flying in their last direction of movement (while still being in stone form)?