Ok, I have been re-watching S02 finale (i think for the 10th time, i lost count) and we all know what happened when the fail-safe was triggered by Desmond. We know what happened to Desmond, Locke, Eko and Charile, and the rest of the people on the island.
BUT, the question now, is this it? what effect does (or did) the fail-safe have on the time-line?, did it move the island (in time)? did it reset something? I remember in S03 reading funny theories that Bernard & Rose were turned into Nikki and Paulo because of the fail-safe, but of course this one have been refuted.
But that crazy theory worked well with the whole time-movement-high energy pockets story. Because if the effect of the fail-safe was just turning the sky purple and sending person who activates it back in time, then they would have done it long time ago.
Therefore, There must be a gigantic and a determintal effect of the fail-safe, and that effect is the reason why it is an absolute last resort (and why it was never mentioned in the orientation film).
So, any ideas/theories on this? perhaps something you know that i don't
Thanks and Cheers,