I think it's rather ironic that Parcells get criticized for getting angry that Belichick welshed on his deal to coach the Jets...yet Belichick (& the Pats organization) has a pretty bad reputation for not wanting their own people to leave. He's apparently very angry that Mangini left to coach the Jets & refused to refer to him by name at all last week leading up to the game. (And the Pats have tried to institute a league rule that's been nicknamed "The Pioli Rule" aimed at preventing staffers--like Scott Pioli--from leaving a team. Kraft keeps trying to get it passed.)
Say what you will about Parcells, but he's always allowed--& encouraged--his guys to take HC jobs.
It's also ironic that the vaunted Belichick isn't doing so well without Weis, Crennell, & Mangini. Do we now start claiming they're responsible for his success? (Since so many keep claiming that Belichick was responsible for Parcells' success.)