DOC JENSEN: Another popular theory making the rounds is that we're dealing with alternate realities. For example, there are people who think the flash-forwards are merely possible future scenarios, not written in stone.
CARLTON CUSE: We want people to believe in the stakes of the show. The problem with alternative realities is that you never know when the rug is going to be pulled out from under you. We want the audience to believe that the jeopardy is real. Postulating alternative realities would be an escape valve that would be damaging that as a narrative value.
DAMON LINDELOF: You can get away with it in Heroes, where there is an apocalyptic future you want to avoid. But we're doing the opposite. We want to work toward a future where Jack is absolutely miserable and wants to go back to the Island. Everything we present to the audience has to be factual.
CUSE: We want the audience to believe that is THE future. We don't want people thinking, ''Well, since there are five iterations of this, I'm not going to invest in what's happening to the characters.''
LINDELOF: We're not going to tell you that we're against bending the time-space continuum. We are very for it. Carlton and I are PRO time-space continuum bending! But we're ANTI-paradox. Paradox creates issues. In Heroes, Masi Oka's character travels back from the future to say, ''You must prevent New York from being destroyed.'' But if they prevent New York from being destroyed, Masi Oka can never travel back from the future to warn you, because Future Hiro no longer exists. Right? So when we start having those conversations at Lost, we go, ''This show is already confusing enough as it is.'' To actually have characters traveling through time has to be handled very deftly.
CUSE: For example, the fifth episode of the season [airing next week] deals with time travel and operates in different time periods. It was a tough story to break. But we adhere to our rule: no paradox.
Here is the complete discussion on MPU. I know this thread is about time travel but I believe much of it if realative to the discussion.
We all know there is some kind of time issue on lost, Desmond episodes have proven it. Where I come into disagreement with people is that they try to explain everthing with time travel. It just is not gong to be that big a part of the show. IMHO.
To me the key is NO PARADOX. PEople traveling to the future and coming back causes a paradox.
I like what others have been saying, Time is screwed with, some time may be "lost" but that does not mean jumping to the future and past to me.