Theory:Doctor Who television discontinuity and plot holes/The Pandorica Opens

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Please discuss only those whole stories which have already been released, and obey our spoiler policy.

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

Remember, this is a forum, so civil discussion is encouraged. However, please do not sign your posts. Also, keep all posts about the same continuity error under the same bullet point. You can add a new point by typing:

* This is point one.
::This is a counter-argument to point one.
:::This is a counter-argument to the counter-argument above
* This is point two.
::Explanation of point two.
::Further discussion and query of point two.

... and so on. 

• 5145 is not in the 51st century.
• While scanning Stonehenge, how did River Song miss the Cyberman head?
• How is the Cyberman able to function without a head inside his "helmet"?
• How is a Roman Gladius able to penetrate a Cybermen when 21st century firearms are not?
• If the trap involving Romans, Pandorica and Stonehenge was built from Amy Ponds memories, why are there pieces of Cyberman scattered around?