Okay, he might not poof, but he can't answer either, and a non-answer is an answer ;P. My logical setup was not F->T, it was F->no longer a simple yes/no question. Your example is a case where the premise is always false, in which case the statement itself has no inherent meaning and therefore you can manipulate it as you will. The question I used I posed is either true or false, in the case it is true, it is a yes/no question, but if the first part is false, then it is not a yes/no question.
I.e. if I asked you:
If you are going on vacation this month, are you going leaving for more than a week?
If the first part is true, then it is a simple yes/no question. If it is not, you would answer with, like, "I'm not going on vacation this month" or sth. If you answered yes or no, it would indicate you are going on vacation this month.