Eyeglass

It's the hair! This is more of a confirmation of other theories that people have come up with before me. I am a bit late in getting into the game. While I was trying to discern how sherlock survived the fall I was looking for clues to confirm if it was actually sherlock on the ground, that might point me in the general direction of his methods. A first glance I noticed that the coat that is on the body is the same as sherlocks, the upper left button hole has the same red outline as when he is standing on the roof, so I figured there was some way he broke his fall and perhaps drugged himself to appear dead. This would eliminate the body double theory. However clothes are easy to fake, hair isn't. If you look closely the hair on the corpse is slightly different than sherlocks. I would says this is confirmation that there is indeed a body double.