I'm still thinking about the BBC radio adaptation of The Devil's Foot. It has me more convinced than ever that Coules was intentionally queer-coding Holmes. The constant references to Tristan and Isolde just kill me. This quote from the opera especially:
"So let us die and never part. Together for the rest of time. No more waking, no more fearing. Nameless, endless, loving, sharing."
And the fact that Holmes and Watson said the last line together (in Holmes' mind after they poisoned themselves), just like Tristan and Isolde did while in each others embrace. Now I don't know all that much about opera, but I do know the major plot point of Tristan and Isolde is the two of them drinking deadly poison and it turning out to have been switched with a love potion that cursed them with forbidden, tragic love. Why else reference this specific story if not to suggest that Holmes and Watson, too, have a forbidden, tragic love?
So that got me thinking: what if Holmes had been in the habit of repressing his feelings? Maybe for so long that he didn't even realize the truth of them himself, and it was only at the moment when Watson saved him that he became consciously aware of his love for him (after he had "drunk the love potion" if you will). Once Pandora's box was open it could never be closed again. The above line showing up in Holmes's poison induced hallucination indicates that Holmes' biggest fear was that his love for Watson would destroy them both.
After this episode, he started complaining of getting distracted and/or slow on his cases. It's giving: "Dear mother I cannot weave, slender Aphrodite has overcome me with longing for a girl." (Not to quote Sappho in reference to gay men rather than lesbians, but if the shoe fits.)
In the very next episode, His Last Bow, we see that at some point Holmes completely isolates himself from Watson. They hadn't seen each other in years and it was entirely Holmes's doing. Why would that be the case? Perhaps he was trying to save Watson from himself? Or he just couldn't stand seeing Watson married to someone else? He does start to pull away from Watson after two things happen pretty much simultaneously in The Three Garridebs: Watson gets engaged again, and Watson gets shot.
(Disclaimer: I am a little confused about the timeline in the radio show, it kind of jumps around, so I could be wrong about some of these points)
Anyway, that's just the story that I'm getting from this episode. Like I literally could not figure out a heterosexual explanation for this shit. I eventually realized that the Tristan and Isolde stuff was probably intended to be about Leon Sterndale and Brenda Tregennis but it fits Holmes and Watson's relationship so much better.
(Also, random aside, I just want to point out that Watson said Isolde's lines. Note that Isolde is a healer who, before the beginning of the story, healed Tristan's wounds. So make of that what you will.)