I know this has been reiterated SO much lately, what with everyone and his aunt coming up with theories. At this point, if it's written down here, it's probably been written down about ten or twenty other times in other places.
My reasoning is mostly on the crazy crack in the wall. Hear me out and comment? :D
Cross-posted to
doctorwho The cracks aren't erasing time, they're erasing memories and existences. What is our existence without memory to hold it in place?
And now, a word from our friendly Fifth Doctor: "A man is the sum of his memories, you know. A Timelord even more so."
There's been a HUUUGE focus on memories this season.
- young!Amy kept her memories of the "raggedy Doctor" so strong (pictures, dolls, dressing up Rory like the Doctor, etc) that she was sent to psychiatrists.
- Amy chose to press the 'forget' button, whereas the Doctor refuses to forget the events of the Time War (and of his actions) despite the pain it causes to remember.
- Amy's a time traveler now, so she was able to remember the Clerics who were sucked into the crack. I assume she can remember the Weeping Angels as well.
- The bomb in the cyborg that the Daleks built was stopped by the memories of a life that never quite existed.
- The Doctor has been telling Amy to remember - about the Daleks and the Cybermen, about what he told her when she was seven, and now about Rory.
- The Doctor also said that the point wasn't that he wouldn't tell her what he said, it was that she had to remember.
- The relationship between the Doctor and River Song is built purely on memories of events that happen in the wrong order for both of them.
- I'm pretty sure you can chalk up the dream-worlds in 'Amy's Choice' as memories.
More specifically, the crack is centered on the exact day of Amy's wedding, not just her. Which in of itself should be a huge memory. I'm inclined to believe that the wedding is one of those 'fixed points in time' that the Doctor keeps bringing up. Weddings require both a bride and groom; ergo, Rory can't be perma-dead/erased.