RealGM

I've noticed a lot of threads comparing players by PER, WS/48, etc, but never seen ORtg minus DRtg used. Would this be a valid, useful number? I'm not that up on the latest and greatest advanced stats but I think you can pretty fairly judge by PER, WS/48, etc. and the eyeball test. It seems most players (well really I've only checked a few ) that have great PER's, etc. also have a difference of 15-20+ in their ORtg and DRtg. Is this redundant or just a worthless number?

I just kinda recently noticed this as I was checking Dirk's numbers compared to Duncan, KG, Barkley and Malone and again, he compares favorably to these others in this number. I've heard about +/-, RAPM, etc but don't know from where they come or how to use them.

It's not a bad way to rate players, but probably a little worse than RAPM.

If you do indeed use it to rate players, just be aware that players with 15-20 difference in ORtg-DRtg don't lift their teams by 15-20 points per game (over an average player). Real superstars raise their teams by ~7 points per game, so whatever results you get with ORtg-DRtg, you'll have to divide that number by ~2.5 to see their impact on team point differential.

The biggest flaw of this rating would probably be that it gives bigs on good defenisve teams a very low(=good) DRtg, even when that team defends better with them on the bench