"Should it be something we can give to him or not?" he asks. "I'd mentioned it in the context of something I never intended to do in the first place, but I told him as much and I wouldn't want to be too predictable."

On the other hand, he wouldn't want to give Tony the wrong surprise at the wrong moment, either. He has a clearer sense of Tony's limits now, of course, but Sherlock is the one with more experience in pushing them.