Cyanide

But, its hard to tell whether Faraday was:

1) intently lying about altering the past
2) incorrect about his assumption regarding altering the past
3) broke the actually physical laws of that universe by the nature of Desmond being "special"

2+3 seem more likely based on the fact that Dan doesn't seem to think about the opportunity to talk to Desmond until he notices that the anthropologist lady has a bleeding nose...similar to Desmond when he was warping back and forth in time. This "reminded" him how Desmond was "special"...in the sense that Desmond has warped back and forth in time and has been able to alter the past. If that were the case then maybe Desmond's split existence allows him to be altered in any timeframe we consider. But, that doesn't alter the point about altering the sand beneath everyones' feet.

In fact, they should all be considered "special" now as they have all moved back and forth through time. And, they brought some things with them (clothes, the boat etc..). Mind you, Desmond's time-travelling was of a different sort; he didn't "appear" ("Pop") in new timeframes in new locations, he more "invaded" his own body with a "present-derived consciousness" which proceeded to take over all cognitive function for that temporary period of time while it was invading.

The only plot-saving plausible option involves Faraday either lying or being incorrect in his assumptions.

Cheers

Cyanide