But in a comparable hypothetical scene on TV, the McGann and Hurt incarnations would almost 100% certainly be represented by archive footage from Night and Day of the Doctor, in exactly the same way that the Changing Face of Dr Who montage has happened since the show came back. They've never shot new footage for those montages, to which the Weapons of Past Destruction example most closely seems to compare.
Just for comparison, over at the Complete Marvel Reading Order, in the context of flashbacks and such, we generally define an "appearance" as specifically having to be something that contributes new information, however small, to the story of that particular character. By that measuring cup, the examples from this thread:
- The World Shapers: Assuming that's exactly a scene from The Invasion: Not an appearance.
- The Then and the Now: We learn absolutely nothing about how the past (or future) doctors experience this event, but it is a new event that happens to them nonetheless: Yes, an appearance.
- Petals: A visual representation of what he's talking about -- on TV, I think you'd use audio clips of the past Doctors mixed into the soundtrack -- but it's not a new event: No.
- Weapons of Past Destruction: Unless the rest of the story illuminates events that happen to the McGann and Hurt incarnations, this is merely a visual representation of what the Doctor is forced to remember: No.
- The Transformed: Tricky, but it's still no new information. Nothing is happening, here, it's more representative of Mickey's relationship with that Doctor compared to with his previous incarnation.
- Hacked: New information. Clear appearance for everyone involved, so: Yes.
- The Fountains of Forever: Obviously: Yes.
- The Arts in Space: The Doctor and Romana don't appear, a portrait of them does: No.
- Unnatural Selection: None of these characters appear, only photographs or other in-universe still image depictions of them: No.
- The First: I'm not familiar with the story, but from the image presented here, there's nothing new here: No.