Theory:Doctor Who television discontinuity and plot holes/Resolution


 * Why does no one seem to remember the Dalek invasions of 2007 and 2009? (Doomsday (TV story), The Stolen Earth (TV story))
 * Bluntly, just lazy looking after of previous continuity.


 * In series 5, the Doctor was surprised Amy couldn't remember the 2009 Dalek invasion. It was revealed later on that the cracks in time had erased the RTD-era invasions (and possibly some classic ones). This is why it wasn't common knowledge in the Moffat-era that aliens existed and why Graham didn't believe they did in The Woman Who Fell to Earth.


 * Those events were not permantenly removed from the timeline. What did captain Brooke do then? How did Davros have footage of that event? And why is Rory suddenly back but these events aren’t? Cracks didn’t wipe it for good. It’s an assumption that made the writers wrongly not get pulled up for their bad connections.


 * Not really. Big Bang 2 completely reset the universe so it makes sense that some things were rewritten. Plus, it's all 'timey wimey' anyway; some points are fixed and others aren't. But, to answer each of your attempted counters: 1) Brooke is unknown, but we don't need to know. Afterall, the episode occurred in 2019, so it does not contradict what happened in the 2050s. 2) Davros is a genius, so naturally he has technology capable of viewing messages/footage across all of time and space in all various realities/timelines 3) Rory was different as he'd travelled in time and was a single individual rather than an entire event; the Doctor has previously established time travel affords one a special kind of protection. Plus, the Doctor reset the universe so he had some power over exerting how the universe banged back in to being.