I never considered Jay a serious candidate -- despite what Yahoo! might think -- simply because the timing is awkward as hell trying to go from the NBA to college.
Unless Stevens was going to let him out of his contract, and I doubt seriously he'd be willing to do that, we'd have to wait until at least the end of the NBA regular-season to finalize the hire and have Jay start assembling a staff. That's assuming the Celtics miss the playoffs, which in the dog-sh!t Eastern Conference is difficult to do.
No matter how much we may want the guy, no way you can basically idle your program for two months. Gotta hire a head coach, let him hire a staff, then get them out re-recruiting our current players and recruits ASAP.