I'm not enough of a student of the game statistically to be able to answer questions like that. And in addition to what I performed, the best analysis would go back over multiple seasons.Zipp
I have always thought that first downs, or difference in first diwns, is an important stat. Did you happen to look at that?
One thing I can say is there's a reason they call yards gained/allowed "TOTAL offense/defense". They bake in a lot of stats themselves. If you don't produce first downs, you don't usually rack up yards; and if you give them up, you allow a lotta yards.
You also can't just focus on one--gained or allowed. That's why NET gives you a higher correlation with results IMO.
Ask me again next summer, and maybe I can crunch an analysis of what you want in the off season, assuming we get one!...