http://knickerblogger.net/statpage/2011/index.htm
Code:
Team Win% Exp. win% Difference
Spurs 0.871 0.760 +0.111
Mavs 0.800 0.693 +0.107
Lakers 0.688 0.708 -0.020
Celtics 0.800 0.768 +0.034
Heat 0.735 0.799 -0.064
Exp. win% is expected win% (or Pythagorean win%), and is based on efficiency differential. It's historically a better predictor of future results than record alone, or even point differential alone (because exp. win% accounts for pace).
Maybe Chuck's on to something; the Spurs and Mavs aren't quite as good as their records show.
The most overrated team in the NBA? How about the Chicago Bulls, who are 20-10 but have an efficiency differential of 0, meaning that they're really performing like a .500 club.