Good idea. I do seem to recall he stopped using at some point. If he was self-medicating, I wonder how odd Holmes thought it when suddenly he didn't need to the drugs for their original use once he had this new flatmate. Of course, at that point he was just plain addicted, but it would definitely stir his interest.

And Blair would undoubtedly be interested in seeing these notes of a doctor and a detective in Victorian England who who were left figuring the situation out from pure experiment without having any of the research.