After Charlotte disappears, Daniel keeps on saying that he 'won't tell her'. Since Charlotte told Daniel that he approached her and told her she would die if she ever came back, perhaps Daniel is thinking that if he now chooses NOT to do this, then that proves that the past (and hence the future) CAN be changed. Any thoughts?
Ultimately I don't think it will matter because telling or not telling her had no effect on the outcome of events. That said it does kinda throw a spanner in the works of the what happened, happened thing.. and Daniel isn't Desmond so he is still having to follow these rules.
Daniel is one of the few people around who understand Desmond's significance in this regard. But even Desmond can only bend the rules, then the universe course corrects (RIP Charlie) and Daniel understands this as well.
I think Widmore and/or Ben are the only dudes who might try to use Desmond to severely mess up the universe - especially if they come to the realization that they can never regain control of the island. I think "the war" will come down to one (or both) of these players trying to screw over fate and unravel the timeline by doing so - Desmond and Daniel both have the potential to be pawns in all this, I guess.
I think he will try to change something and...
1.) he eventually realizes what he must do and still tell her as to not disrupt time/space.
2.) causes "the incident" in the process.
Well this is exactly the problem with time travel. The Whatever Happened, Happened rule is fine so long as characters are not aware of their specific fates. But once someone is made aware of what is 'supposed to', or indeed what 'has always and will always' happen, they could change it. Daniel is a free-thinking conscious being. He has the freedom of choice NOT to tell charlotte anything, despite the fact that Charlotte tells us he did. If Charlotte had not told Daniel his own future/her past then I can understand how he would be powerless to avoid it. But since he now KNOWS that he talked to Charlotte in the past, what's to stop him choosing not to now. And don't just come back to me with 'what happened happened' again, I want a serious discussion of this. Because I believe these are exactly the sort of questions Daniel (and the show) are going to be dealing with in the episodes to come.
We have a couple people that could try to change the rules in all of this. My thinking is that Jin is a very important player in course correcting this line of time. He was not on the list from Ben to Michael in season 2 for a reason I believe.
Possibly that reason is that he died before Ben learned who he was.
Or perhaps that Jin is Jacob and to keep his love Sun from returning to the island he found it necessary to exclude himself from the list.
Or perhaps he wasn't supposed to have survived the explosion after all.
Either way, Ben did everything he could to get Juliette back to the island (see discussion in "the other woman" between Harper and Juliette about Juliette reminding Ben of "her"). Did everything he could to keep Jack, Sawyer, Kate, and Hurley together. But not too many times have we seen Ben interact with Jin (or at all - kind of foggy on that). Also I think that at the time Ben didn't realize the importance of Locke to all of this.
So the war that Widmore was mentioning is probably the Purge and that is what needs to be broken - so who will be in the best position to break it from the timeline. Clearly Locke is the logical choice (but not sure what time he is in right now) but I am leaning towards Jin.
Fate, the universe, God.... whatever you want to call it. Michael couldn't kill himself - not for a lack of trying.
But unless some higher being/God/Fate physically takes control of Daniel then there is nothing stopping him from speaking to Charlotte or not speaking to Charlotte. I have the same thoughts about "what happened happened" that other people are having. Yes I think it applies to certain situations, but when you are aware of what you're "supposed" to do, then I believe yes you certainly can change it.
Maybe the universe could course correct, but I don't see how that would be possible in this situation being that it was Daniel and Daniel alone that talked to Charlotte.