At first I was angry with Sherlock for harassing Trevelyan with the gypsies, but then I realized it was what he needed.

The gypsies are totally Sherlock's back handed way of showing affection. Q knows it, too, but it took awhile for him to realize that implying he didn't belong with them was actually saying 'I'm glad you're here' in Sherlockese.

Thanks for reading and commenting!