I didn't read this entire thread and I don't know if this had been said before..
I got a theory that explains everything happening in Lost right now??
The theory is based on these points:
-the past can be changed
-if the past is changed, the present will be affected in accordance with that change
-but the memory of the people in the present will not be affected (which means it is still dangerous to change the past)
Example:
-I'm holding a ball with Jordan's autograph right now
-But my brother went to past to get rid of Jordan before I could ask him for autograph
-Then I'm surprised the signature suddenly vanished. My memory was preserved. But the material is not.
This explains Desmond's sudden remembrance of a memory which never existed in his memory before.
Furthermore, it seems when you go to the past, you are actually creating a separate time dimension which is in parallel with other dimensions. Let's consider my first example again:
-For example, my brother went to past right now.
-For every second which elapses in my dimension, the same number of seconds elapses in the new dimension
-After 300 seconds since he arrived at the new dimension, he successfully get rid of Jordan
-After 300 seconds in my dimension, the signature disappears.
This is the reason why Desmond hasn't remembered it exactly at the time the others started time-hopping.
Also, observe the same number of years have elapsed for both the present dimension and Sawyer's current dimension.
Now, for the more confusing part..
-Whenever the past is changed, the present is only changed at that very instant as well
So going back at my first example:
-I'm holding a ball with Jordan's autograph and a video camera right now. The cam is focusing on the signiture.
-But my brother went to past to get rid of Jordan before I could ask him for autograph
-Then I'm surprised the signature suddenly vanished. My memory was preserved. But the material is not. I rewinded the video and I saw it captured the vanishing of the signature..
This explains Locke's revival I guess. Somebody went to the past to prevent his death so the Locke in that dimension will not experience death. But the Locke in the original dimension still experienced death but was revived.
But then, if you fully understand what I've just said now, you'll realize that with this setting the Others should have no prior knowledge of the survivors before the crash. Just like in my previous example, if you only have a camera filming the entire happening in that island since 1950s, then the Others shouldn't have known the survivors before the crash even though some of these survivors met them in the past.
The explanation I can give is a bit more confusing:
-Whenever you create a new dimension, you can still create another dimension from that new dimension. It's recursive.
Example:
Dimension 1: The Others don't know the survivors prior the crash. Then, survivors arrived.
Dimension 2: Some survivors went to the past in this dimension. They met the others. The Others did research on the survivors. Then, survivors arrived. Remember that this arrival happened because it happened in Dimension 1. The only difference now is that the Others in this dimension knows the survivors prior to the crash, unlike in dimension 1.
Dimension 3: Here is where Sawyer and co are in right now.
So this means the from Lost episode 1, all are happening in dimension 2. And the 1977 dimension where Saywer and co. are right now is dimension 3.
Well, this is just a theory. But this makes the most sense for me. I hope I explained everything clearly.