MIB went home by LostInHouse

After watching the finale again, I realized something. The Island Desmond and MIB were both confused on how they were supposed to GO HOME. MIB thought he could go home by leaving the island. Island Desmond thought he could go home by going into the light of the island. But the opposite for each was true. Let me explain:

Desmond was our clue to understanding what MIB / Smokey meant when he said that he wanted to go home. When Widmore shot Desmond up with a full blast of electromagnetic energy, I think a that island Desmond's consciousness switched places with the Desmond who was still "LOST" in the sideways world. In the sideways world, when Charlie helped Desmond to "remember", Both Desmonds were enlightened. Everyone is the sideways world who had been enlightened were waiting for the other LOSTIES to join them before they could move on.

So, the already enlightened Desmond was on the island instead being in the "waiting room". He was no longer afraid. He was just waiting for his friends so that he and Penelope would move on into the Light. That is why Desmond was guessing that MIB was taking him to the "Bright Light", - so he could finally go home. But this Desmond was in the wrong world, and the Light that he saw did not take him anywhere.

The Desmond in the sideways world was going against Mrs. Hawkings warnings because he was trying to Speed up the process. He knew what was waiting for him and Penny, and he did not want to WAIT for the others to slowly "Wake UP". So Desmond began "helping" them remember things more quickly.

Did Jacob send Desmond to the island to help "free" his brother from his worse than death fate of being a Smoke Monster for eternity? I think so. The Light and water formed a barrier in the heart of the island that Smokey could never cross to go "home". That is why the Smoke Monster was "trapped". But MIB's soul was trapped inside of Smokey and so, MIB was just trying to leave the island and go across the sea just as he did when he was living.

Smokey has never been able to cross the water in Smoke form. So, Jacob needed someone who would be able to remove the cork and drain the water so that Smokey could return to the bowels of the island. To do that, this person had to build up enough resistence to the Electromagnetic Energy so that they could survive long enough to pull the cork out. Once the Cork was removed, the evil fueled by the magnetic energy was returned to the earth and MIB became mortal. Once MIB was mortal he could die like anyone else, and his soul would be free, and so it was.

But now, the island and the Life giving Light were in danger of being destroyed. Jack, did the job he was convinced was his destiny. He fixed the island, saved the world, But more importantly, He fixed himself and he protected the Light....

The same Light that would lead them all home in the end.

Without the Light, they never would have found each other again. And that is how the two "worlds" were able to merge together.

Jacob WAS a man with a plan from the very beginning. Kudos to the writers for that.