For the whole 05/06 season: 1 % higher fg on offense = 4.5% higher win. 1% lower fg on defense = 4.6% higher win.

Looks the same to me. One interesting note though, the R-squared is better for defense (.17 off vs .31 def). (which doesn’t mean the effect is greater, just that is may be a little more predictable from one team to the next).

In the end, I still think the issue is that teams don’t just create fg%, they must pay players to create them. So the costs of being more offensive-minded (getting iverson) or defensive-minded (getting wallace) are the primary driver. How to get the most bang for your buck?

Your argument based on variation of results from offense vs. variation of results from defense is legitimate regarding regular season performance and is enhanced in the playoffs, since all playoff teams have at least a couple good offensive players. But the real root of the effect is that playoff games often come down to the final play(s) because most of the time playoff teams are fairly evenly matched.

Now a team’s shooting performance on a given night (or in a given play) is largely a matter of chance, but playing good defense is closely tied to effort. Thus strong defensive teams can directly control their (defensive) performance, and in particular they can be sure that they perform their best when it matters most–in the playoffs and at the end of games. This is not true of offensive teams, who are at the whim of Lady Luck.

In stupid sportscaster talk, championship teams are thus those “who can get stops when they need them.” Unfortunately I learned this first-hand a few years ago as a fan of the Sacramento Kings, who perenially lost nail-biters to the Los Angeles Lakers because of L.A.’s superior defense.

(By the way, note that there is the coupled issue of whether it’s better to have a couple superstars or a bunch of good players, but that merits its own discussion.)

Good offense may or may not result from good teamwork. But good teamwork is a prerequisite for good defense.

Also, I think the PPG stats are too simplistic. Let’s say team A wins 120-100 and then loses 110-100; team B beats opponents by 104-100 and 106-102. By that measure, team A is superior in points for (115 vs. 105) and points allowed (100 vs. 101), yet has a worse record.

Also, if you are using 06/07 data, that comes to 7 whole data points for each team! Maybe some sample size issues there? Looking at 05/06 in full would be better.

j/k. The actual problem is that bad offense is boring. Good defense can be thrilling.