John has revealed to be the smoke monster, so any theory that says otherwise at this point is either wrong or the writers are misdirecting.
John = MIB
John = SMOKEY
SMOKEY = MIB
But has anyone considered that the reason "John/MIB" knows what John is thinking when he dies etc, and seems to have to become smokey without anyone seeing him change to it, is that he is an alternate version of John? I mean with all this sideways flashing there must be some reason for it.
I doesn't seem to make sense that John/MIB has to be out of sight when smokey comes into the room. Plus if he can become smokey why would he fear being shot. Then again a simple knife kills Jacob...vulnerable in human form maybe.
John/Mib wants to go home,...leave the island? Surely if he knows John's memories, has taken the appearance of christian etc, then he must know about the Donkey Wheel, he could just move it and leave...unless he wants back to his reality.