Tonight, Rondo had 2 points (on 1-3 shooting), 10 assists (with only 2 TOs), 7 rebounds, and a steal in 32 minutes. His +/- was -11.
'Melo had 22 points (on 9-20 shooting), 5 rebounds, 3 assists, 3 blocks, and 1 steal in 39 minutes. His +/- was +1.
Jose Calderon had 9 points (on 4-10 shooting), 7 assists (with 1 TO), 3 rebounds, and 3 steals in 33 minutes. His +/- was +11.
Quincy Acy had 0 points (0-1 shooting), 4 rebounds, 3 assists (with 1 TO), and 2 steals in 17 minutes. His +/- was +16.
After PER, the +/- stat is the most useless and disingenuous statistic. According to your logic concerning +/-, Quincy Acy had a better game than Melo, Rondo, and Calderon. Moreover, your logic dictates that the Knicks performed best when Acy was on the floor...even though he only played 17 minutes.
Don't ever bring up that statistic again to measure how good a player is (or to knock a player).