It's violating like every rule of decent TV writing that Moffat really should know by now. Nothing makes any goddamned sense. There's no point in theorizing because the beginning has no relation to the ending and none of the clues add up to anything in a coherent way. What dramatic tension is there? Anything could get resolved out of the fucking blue by some new deus ex machina.

The love triangle is getting House-esque in terms of contrived-conflict-to-generate-tension. You know nothing that happens here will have any bearing on the ultimate resolution of the plot.