Theory: How MiB became Flocke by 3d-aholic

Many people assume that MiB took over Christian in the same manner as Locke. I don't believe thats the case. I think we have two different things going on here.

Claiming a piece: MiB can claim any person on the island that dies and that is not buried under ground. I think generally people are beginning or already do agree with that. However, in that agreement, we know that the person's "physical body" is "used up" in the process. Christians body was never found because it was "used" or became "infected" with the sickness. His body became a walking zoombie. the same is true now for Sayid and for Claire. Their bodies are clearly "used" and remain in tact.

John Locke is "clearly" different because his body still exists and is unburied. The person "walking" around in the appearance of Locke is not the one in the same person. The situation is clearly different. This begs the question for some of you. How did MiB become John Locke in this case as opposed to the other cases?

My theory is quite simple.

Christian (MiB spirited) was in the wheel room when John Locke turned the wheel. MiB fused his soul with John Locke at the moment John Locke turned the wheel. His "spirit or soul" for lack of a better word was riding inside of John Locke during his entire time "off-island". Once Ben killed John Locke, the spirit of MiB took control over John Lockes body and he rode the body back to the island. Once on the island, he was able to take on the complete shape and form of John Locke without needing his body anymore. His soul is now "fused" with the original soul of John Locke in a wholy and complete different manner than the other zombies.