Agree with all the above. Hurley reads the Expose script and exclaims...wow, all along Mr. La Shad was the Cobra. Yet, that is foreshadow. Someone who all along seemed like the good guy was the very person he was always trying to catch. So, who is trying to catch somebody? Nobody yet, except Locke does appear to be a self-appointed evangelist for the island. Also, who have the Others not met (seemingly, they would know the great man if they saw him? They've held Jack, Sawyer, Locke, Hurley, and Kate. They tried to take Echo (plus he's dead, for whatever that means). Desmond, however, has had no contact with any of the others except for Ben. In addition, Desmond is the only one who has been told that he will never be great unless he goes to the island. Finally, Desmond is the only one shown so far who has a clear gift for precognition and the ability to travel in time/reality.
So, who is the real Desmond? Why did he end up in prison? Did Penny's dad tick him off on purpose, knowing that he would inadvertently produce a great man?
Further, Desmond appears to be the only person in the flashbacks who doesn't have a completely messed up (was going to use the f word) life.