Ok, since we all know the Gospel here, is divorce and remarriage permissible? Because the Catholic Church has been giving out annulments -- divorce by a different name -- like party favors for decades. 
Is pre-marital sex permissible? How about heavy petting? I wouldn't want to ask people in church too many questions on that score. 
In fact, there are lots of very common sexual practices about which the Church remains curiously silent, although it can be quite vocal about same-sex issues. That leads me to believe that the Church's attitudes have more to do with taboos than anything else.
So I can't agree we all know the answers to all the questions sexually active people ask, and I can't accept the idea that James Martin is wrong to ask the same questions.