Exactly.
If people would say “of course Ed is Cecil but let’s play the game” I wouldn’t mind. But both Una and Dex went out of their way to dissemble. (Another word I don’t get to use enough.) I wouldn’t accept Una’s weaseling on the subject from anybody else, so why wouldn’t I call her on it?
I know that Sherlockians like to pretend that Holmes was a real character and that Doyle was merely Watson’s “literary agent.” This is great fun in its place. However, if one of them were to look you in the eye and insist after the meeting that Holmes was real and that you were an idiot for saying otherwise, you’d have to restrain yourself from punching that smirking face in.
The behavior here is not about sharing a joke. It’s about telling us that we’re idiots.
Hey, Una, Dex. You’re acting like jerks. Isn’t a warning due at a minimum? How about a full banning?