Can we just talk about Martin Freeman? Like, we all just accept that John is so moved. We all go "awwww." But we can only do that because Martin Freeman is sitting there like a pro, BEING John Watson, making him real.
HUGE Spoilers... Well, worth a read, anyway... Went rounds on Reddit. Figured out almost all of this, and then someone got on and pointed me in the right direction. Great theory. Explains the only thing I couldn't understand. And takes it back just a little bit farther.