Musburger may not know the rules real well, but he doesn't really dog the officials like other idiot announcers. I don't know if he went to umpire school or just started out calling baseball at the amateur level, but he has officiated -- at least for a time.
I just laugh when I hear all the complaints about BM. No, he isn't the best play by play guy, but he's pretty good. He's a bit over-hype-ing if you will. Sometimes he gets on kicks where you want him to move on. But he's nowhere near as bad as many think he is, and frankly, to me, the complaints about him on message boards are from people trying to show how cool they are (or how enlightened they are) by dogging him. Give it a rest. If you don't like him, fine. But he's ABC's top guy for a reason. On the old NFL Today, he was money. The guys today are unwatchable.