It’s Sherlock when he was younger! Maybe this is how he sees things while he plays: he focuses in on specifics floating before him against a background he conjures.
Writing prompt: What is going through Holmes’s mind when he plays the violin? How do you imagine it? This doesn’t have to be Sherlock fanfiction, not at all. It could be the thoughts of a genius with a completely different personality and professions or an alien hivemind. (Of course I had to throw in a little science fiction. XD)