Have they said much about why a lot of the pre release stuff isn't in the game, or was shuffled to significantly different places? The 'Revenge of the Jedi' tear ends up right at the start of the game and very different from the old E3 demo, and I remember something about a postman you could save which isn't in there. Was the game changed significantly, or were they deliberately building red herrings? The moment when the Songbird takes Elizabeth is significantly different to a prerelease demo, for instance.
Irrational claimed that they essentially made five or six entire games over the course of designing Infinite.