Mo Williams is Cleveland's missing piece, so says ESPN's Daily Dime. Meanwhile...
The +/- stat measures how a team performs while a given player is on the court. For instance, C.J. Watson had a +24 differential last night because the Warriors outscored the Bucks by 24 points during his 36 minutes on the court.
Now, the stat can mislead for a lot of reasons; one is because it doesn't take into account how a team performs off the court. 82games.com appropriately strikes a balance between on-court/off-court team performance in its +/- stats. It's not perfect, but it's also not a bad indicator.
In any event, Ramon Sessions is the only Buck with a positive raw +/- differential this season. Often, bad players who don't play much on bad (outscored) teams end up with much better +/- differentials than good players who play a lot on bad teams merely because they naturally get outscored less in fewer minutes.
But Ramon Sessions plays a lot, which makes his +6 even more impressive. If it always seems like guys play better (or the Bucks play better) when Sessions is on the court, well, you're probably just being perceptive. Oh, and as you might guess, the Bucks don't do so well when Sessions is on the bench either. In fact, they are pretty bad.