Yeah, the rebounding is great. However, you get poor defense, poor scoring, poor efficiency, and poor passing.
We'd never see the rebounding, though. The rebounding issue with the Celtics is because of the system, not so much the players. They don't go after ORs unless they are easy ones, in order to get back on defense, and as far as DRs go the C's are perfectly in line with everyone else in the league (last season we got three of every four, which is good for 9th overall, better than average).
I'd argue that this is perfectly fine, since the C's had one of the lowest eFG% for the opposing team, and a respectable eFG% for themselves.
So that being said, seems to me like this guy does nothing we'd find useful at all.