You're not making an apples to apples comparison. Duncan is one of the best power forwards the league has seen in years but he doesn't have the marketability or appeal of the elite players. Spurs play a good system of ball which is largely the reason for their success. They've got all of the tools the Knicks never had from player development to scouting and drafting to coaching. Melo's salary isn't going to hold the team back as long as he commits to team ball.