According to the study, Johnson ranked 14th (between Marcus Thornton and Danny Granger) in the league in Offensive SPM against above-average defenses and ranked 14th (between Deron Williams and Danny Granger) in the league in Offensive SPM against below-average defenses.
Thus, the playoffs notwithstanding, Joe Johnson performed consistently well regardless of the quality of team defense he faced last season. There are two possible (and plausible*) positive interpretations of this information.
- Though the sharp decline of his already below average Free Throw Rate in 2009-10 remains a concern, Johnson didn't just rack up good offensive numbers against bad defenses. Johnson's new contract is still a bad idea long-term but, on the basis of this study, there's even less reason to expect him to decline precipitously in 2010-11.
- The discrepancy between Johnson's numbers against good defensive teams during the regular season and during the playoffs could have had as much to do with Mike Woodson as Joe Johnson. First, though Johnson's overall minutes played were down significantly in 2009-10 (helped by the 6 games he missed) he still played 38 minutes per game and may have been more worn down than the average player in the post-season. Second, it's possible the predictability of Atlanta's half-court offense made it more easily stymied when seen repeatedly over the course of a best-of-seven series. Not to mention that the Milwaukee Bucks and Orlando Magic were the 2nd and 3rd best defenses in the league last season.
Paine's study isn't all good news. He doesn't use defensive efficiency to separate above-average defensive teams from below-average defensive teams. Rather he adjusts defensive efficiency for "home-court effects and the strength of the opposing offense." In doing so, the Hawks drop from 13th in the league in defensive efficiency to 17th.
Putting all the team's resources in the service of re-signing Johnson hasn't allowed Rick Sund to address the team's obvious (and long-standing) defensive limitations though, again, Mike Woodson's absence could lead to some improvement in that area if the constancy of switching screens really was a key contributor to the team's defensive struggles.
*This is new work and the results should not be assumed to be predictive. I'm approaching the data with common sense and good wishes rather than analytically. We figure to learn more in Paine's upcoming posts on the subject where he will break down player performance against the extreme best and worst defenses.
A (god willing) less important negative aspect of Paine's study concerns Josh Powell. Among players with a usage rate of at least 18%, Powell had the second-worst Offensive Rating (ahead of only Daequan Cook) against above-average defenses. Among players with a usage rate of less than 18%, Powell had the sixth-worst Offensive Rating (ahead of James Singleton, Ime Udoka, Vladimir Radmanovic, DeShawn Stevenson, and Sasha Pavlovic). The takeaway: Josh Powell is a bad offensive player and good defenses are good defenses, in part, because they force guys like Josh Powell to use more possessions than do bad defenses.