How about: Should Harry have trusted Quirrell? I don't mean "did it have a good outcome"; I mean, was Harry's trust justified by what he knew? Would you have done the same thing?

In retrospect, I think Harry ought to have said, "Professor Quirrell, I owe you a great debt, and have great respect for you. If you ask me to do something, I'll probably do it. But I don't trust you one single bit." But I doubt I would have said that myself.