I was on RealGM last night and saw an interesting thread.
In summary it supposed that Eddy Curry's imminent return was preventing the playing time of Darko.
Basically it was that because of the money invested in Curry and the fact that we need to dump his salary, we've neglected to play Darko lest he play well. For if he was to play well, then we'd be in a bind without the playing time for Curry.
Dunno, interesting idea about how contract amount and length affect playing time.