Correlations: I'd say that this was a neat character study, except it's so much more than that. I love how subtly you point out some of the fundamental differences between John and Sherlock, and how John sees his actions as protecting something valuable. That really struck a chord.

Problem Like Sherlock: Hee! Of course you solve that problem fastest if you sic Mycroft on it. Love that he's playing along to a point where he's fully aware that the mere threat of his presence is enough to get Sherlock in line. Ish. And the Sussex Vampire! \o/