So was my reaction. But this scene is the sort of scene I expect to find in the middle of an ep. Or the beginning of the 2nd part of a two-parter. Or at the start of a movie or TV show. Not at the beginning of an episode which claims to give us the answers. You only have 2700 seconds for answers, a resolution to the current conflict, a few action sequences and good jokes and a new mystery at the end to draw interest. You don't waste your first 100 seconds on creating a mystery right out of no where. Is there some sort of medium level between mindscrew and big lipped aligator moment? Because that's what this is.
I do believe Moffat is a superior writer to a lot of other writers (Helen Raynor, Paul Cornell, Stephen Greenhorn and Stephen Thompson come to mind. Good thing Thompson never wrote a Doctor Who ep). But ever since he became show runner he has lost his way and fallen into the Davis trap. Cept Davis could survive in his trap. Moffat cannot.
@Starscream: Memento was self contained and gave us a mystery which made sense at the end. S5 & S6 have much in it that did not make sense.
In lighter news I have finally got a fun fact for Closing Time: this ending marks the 3rd "dad and lad" ending of season 6, whereby a father and son are reunited: the others include almost people (where the ganger dad took his originals place) and Night Terrors (yeah). I think there might have been a 4th ending but I don't remember. Or rather, I don't want to remember.