No, guest, the last time I checked I was not mentally retarded, and I understand if you have no particular affection for Doctor Who, but if you're completely oblivious of that reference you must be living under a very culture-reflective rock.
(same guest) see, I don't need an episode crossover, just Cumberbatch and Matt Smith in the same room, having an argument or whatever while someone was filming. I'd love that.
Sherlock Shellingford is the cutest! Milky Holmes is a great series but this is a little biased because that's like including Sherlock Holmes in the 22nd Century as part of Sherlockian mythos or Sherlock Hound or Without a Clue.
Moffat even said he'd like to do it, but that Cumberbatch and Freeman were against it.