I don't think we ever saw Jacob in the cabin, I think it was the other guy from the beginning of the episode that said he was going to **** Jacob; that was the guy in the cabin
That was BBB's theory.
I'm a bit confused here, because was it just me, or did it seem like Jacob's cabin in 2007 that the Ajira passengers went to was the same cabin that Rose and Bernard had been at in 1977? which doesn't add up with the original storyline that showed the cabin was built by Horace.
It also clearly showed the chalk ring around the cabin having been broken. Do you guys remember if that happened when Locke and Ben or Hurley went there? The implication I got was that Jacob had always been at the Statue site, or at least he had been there and not at the cabin when Locke first visited there... and as has been said it was the impostor/locke(?) that was there.
Does setting off the H-bomb imply that Dharma will never return to the island or does it mean that the Dharma timeline gets changed and this change means that the Swan Hatch won't bring down Oceanic 815?
I don't know if it matters, but it creates a casualty paradox. If they had never crashed on the Island then they wouldn't have traveled back in time and Daniel would not have told Richard to bury the H-bomb, nor would they have been there to set it off... which means they don't change the past because they were never there to change it, the incident happens and then their plane crashes on the island anyway.
So far the show seems to have followed Daniel's philosophy that you couldn't change the past/ "what happened, happened", such as how they prevented Ben from dying and Widmore and Alpert remembered Locke from 50 years ago even though it had only been a few days for him and how he saw his own past self and set up the situation to occur that way that he had experienced it.
So the most likely scenario to me is that Miles is right that they caused the Incident thinking that they were preventing it.