I get the he hasn't gotten along part, but that's due to the fact that those guys who "he hasn't gotten along" has this mentality that they are THE guys.
There's no one like that in Boston. In any case, we can probably call him THE guy, as he could be the dude who would score and try to take over when needed.
Regardless of the personal issues, a good player who can score 20 PPG on solid efficiency on a very reasonable contract for practically a late 1st and a player who's not part of the future is a win. Those positives outweigh the negatives to me. At worst, we can still easily move Thomas and get a much better return that what we gave up. At best, he can be a very solid 6th man.
I disagree with Tom Haberstroh, but then again, I'm not an NBA writer...