As a Celtics "regular"... maybe. But compared to all of the Patrick O'Bryants, Mikki Moore's, and Scot Pollard's that have walked through here, Scal really isn't all that bad.
Namely, Scal could play defense pretty darn well. He doesn't give you blocks or steals, but he was just good at sticking with even some of the more mobile power forwards and making them take tough shots. Hell, I even remember him shutting Amare Stoudemire down one game. At any rate he was never "good" but also never "worthless".