Alright, noone liked my idea it was Christian's shoes and all you needed to do was steal them and Smokie will lose his ability to take on Locke's form...
I will add I did finally see the real John Locke was wearing Christian's shoes when he was finally buried. I had been looking to see that for a few episodes, and it was only shown when he was lying in the ground. But also the last thing I saw going into that bag was the shoes that the JLokie was wearing when he "materialized" into Locke's form. He had his shoes off and had pushed them hard down into the bag. And to repeat, that's the last thing I saw go in; and never noticed anything come-out either.
... So Locke was buried with the real pair of Christian's shoes ... Does that mean/mandate the replicas JLokie took off soon after materializing is devoid of magic pixiedust?
And if it's not the shoes, then WTF is in that bag now?
AND WHY IS HE ALWAYS WALKING AROUND A BLACK BACKPACK?
And why does noone else find that he always has that black backpack odd?