I was finding this BBC article on the return of Sherlock moderately interesting (not least because of the 7-minute prequel episode with an amusingly Blinkesque moment).
Perhaps the only awkward moment during the screening was when writer Caitlin Moran, who chaired the Q&A, asked the leads to read out a piece of fan fiction, where fans write dialogue online for their favourite fictional characters.
This particular piece of writing featured the lead-up to an erotic scene between Sherlock and John, but it backfired somewhat as both actors looked awkward reading it out on stage.
Moran apologised profusely for asking them to do it, and Cumberbatch added: "Fans can do what they like but that [a love scene between them] is ludicrous in our universe, so sorry to be all 'eeurgh' but his nibs ain't doing that."
It's such a seductive meme, in our various quiet corners of the Internet, to think that of course the actors in our favourite shows would love our fanfic and share our 'ships. The ensuing dose of cold water in this case is, I think, a salutary one. I'd wonder what Moran was thinking, but it's probably a question best not asked.
(Of course, we can all go on thinking that the relevant actors would love our fanfic. Just as long as we don't put that notion to the test...)
[Goes back to writing Zoë/Isobel fic that had just better not be thrust at Wendy Padbury and Sally Faulkner with a demand to perform it in public.]
ETA (having watched the episode): Ah. That goes some way toward explaining why the topic of slashfic arose, at least.