Remember, Scal was on the bench in street clothes because of how vastly improved the team became over the last year. At the time of his signing, he was projected to be a more substantial contributor... But the C's added KG, RA, Posey, House, Brown, Sam, Big Baby and Pollard in just the last year (Sam and Brown in the last few months of the season)
And I think Scal actually started a handful of games this year and was in the rotation for some of the season, plus you have to add in the "Greg Kite" factor in terms of Scal's value as a hard practicing player... Just saying he's not a total waste of space.