Jared Sullinger is nice kid, and is learning ins and outs. He had some moments, but he cannot defend anyone because of his size right now and really hurting the team. His +/- stats is.... He cannot get his shot off on the offensive end on the likes of Jason Maxille and Kwame Brown. Send him to Maine and he will develop.
Sully is shooting 73% at the rim, a very good mark for a guy that you claim is too short to get his shot off. Dwight Howard as a rookie finished at the rim at a 64% rate, for example. Sully is converting a higher percentage of his inside shots than KG, who is one of the longest players in the league.
I don't think Sully is hurting the team all that much. he's been very solid, displaying a high IQ and a good motor. I thought he would struggle getting off his shot at the rim, but he's converting those shots well, a great sign for a rookie. His mid-range game is weak, sub 40%, but should improve once he figures out what shots to take. He's hit all his FTs too.
Defensively, Sully competes. The refs haven't been giving the rookie any leeway, which is expected, but Sully should improve as he gets more seasoning. I'm disappointing at his rebounding, but he's certainly not any worse than the rest of the boxoutaphobics on the Celtics.