Sorry, but no excuse is needed.
A youngster in Christ, after reading the Book, and then studying the claims of MORMONism, would be able to see that it is a heresy.
Ya don't need to be a Genius or a Geezer to figger THAT out!
True enough, but, and correct me if you think I'm wrong, perhaps younger people are more conditioned by the postmodern "all truths are equal" mantra, and I wonder if the reaction to blazing heresy is somewhat muted in many of them because of this conditioning. I'd be interested to know if Barna or anyone has done any studies on the matter.