I'm not entirely sure why it affected me so profoundly. Technically, it's good but not great. That's not intended as a slam; it's just that I'm used to listening to pianists that win international competitions, so my standards in piano technique are impossibly high. But there's so much love for the soundtrack here, and so much creativity, and I wanted to experience whatever inspired it. This was the piece of fan-art that got me past enjoying Sherlock fannish activity and actually watching the show.
It's a bit weird. As I've been both rereading Arthur Conan Doyle and working my way through the fanfic recs at 221b_recs, I've moved a bit past the hero-worshipping stage and seeing the things that I really don't like very much at all about the show. A great example is the way the show-creators turned Doyle's rather asexual Sherlock into someone who's repressed that aspect of his personality rather than lacking it in the first place, combined with some comments by Moffat that the idea of Sherlock-as-asexual just isn't interesting. Alex pointed me to that comment and, while I'm more than a bit offended by its implications, it's not quite driving me away from the show as I suspected it might. I'd forgotten enough about the original Sherlock Holmes when I discovered the show that I fell in love with these characters on their own terms, and while I'm not convinced they're exactly like the other characters I love in Doyle, they're really separate things in my mind. So I can love the BBC Sherlock on his own even as I get increasingly irritated with the changes Moffat made. I think it's because, while I love Doyle's Sherlock and Moffat's Sherlock, I don't love the second because he's an interpretation of the first. The latter's a wonderfully involving character without having to comment on the former.
Anyway, rediscovering this song reminds me of how I felt when I first sat down and watched the series. It's a bit amazing how little of that has changed, even though I'm much more aware of the show's and show creators' faults in many areas.