Oh my god, I never quite noticed the heartbreaking expression on John’s face in that last panel before.

I keep thinking how terribly lonely it must be to be Sherlock’s friend.  It’s clearly John’s closest, deepest, and most fulfilling relationship, but Sherlock is so singular.  He doesn’t need anyone else for what he does, although much to the surprise of probably both of them, John does seem to help in a sort of muse way.  What’s more, Sherlock goes out of his way to play things close to the vest.  He doesn’t want help; he wants to solve the case and then watch John be amazed, so he deliberately closes him out of the loop.