I raised two kids, and got up with both of them. However, my father never did--or would--change a diaper. Didn't happen in his day. Not knowing Mark's wife, I can't say what she will do. However, I'm not sure how a written contract would set with MY wife. Or rather, I know all too well that she'd never go for it!
Best hint for surviving a crying baby is to get a good set of earplugs. Not the crappy foam ones, but the silicone ones--the good stuff. You can still hear if the little monst...tike is crying, but it won't drive you nuts. Or, at least not as much.
Did you know that the hearing babies of deaf people don't cry? They give up the sport, since it does them no good.