I think that by addressing the issue up front, they really took away any question of whether it's John/Sherlock. The answer is No. Because John's not interested in Sherlock, and Sherlock's just not interested.

And the jokes are there, but, for example that little exchange at the end ("I'm glad no one saw that"), seems to be there because they've hashed it out, and can joke about it. It's not awkward UST, it's two guys diffusing the awkwardness of a stressful situation by joking about something they can both laugh at...

I really don't see how it could be any clearer...

*sigh*