I just want to throw this out here, incase by some inconceivable chance I am correct.

Locke has been dead for a long while before Ben "killed" him.

That's maybe taking Lost theory-mongering too far. :p

It would just cheapen the character completely if it turned out we'd been watching someone impersonating him for 5 seasons. But then again, who knows what twist they'll surprise us with next...

I can't see Locke having been dead before Ben's intervention tbh.

For one, if the speculation about 'The Man In Black' being the Smoke Monster is correct, then we know that the 2 have stood face to 'face'. Also, Locke has been through a lot of 'character building' experiences on the island that wouldn't make sense if it was happening to 'Fake Locke'.

Anyways, I was thinking about Claire earlier.

At first I thought she had died when her house was blown up and that we were seeing her dead like we'd seen Yemi, Christian, etc. Then I figured that 'The Man in Black' had taken on her identity, until I remembered that she was with 'Christian' last time we saw her - taking that 'TMiB' has been Christian all along, then that can't be.

So, where is Claire? She's not in the cabin, we know that much. She's no longer with Christian (if TMiB was 'Christian' and is now 'Locke'). So where is she and what is she doing?

Also, considering that Kate went back to the island "to find Claire", she's done a piss poor job of it. At no point has she even mentioned it!