This is comical, I don't know why PFF has become a go-to citation lately...look at this:
VA Tech allegedly has 3 of the top 5 interior defenders in the country.
Rush yards allowed per game: 87th
Rush yards allowed per carry: 83rd
.
LMFAO
.
UNC, same thing....3 of the top 8 interior defenders.....
Rush yards allowed per game: 93rd
Rush yards allowed per carry: 92nd
.
Boy, those must be some interesting schemes they're running, to be a sieve like that WHILE HAVING THEIR INTERIOR DEFENDERS GRADING OUT SO HIGH.
I know, maybe when they screwed up, they orchestrated it so they'd all screw up on the same plays, right?
I'm afraid PFF is a joke of a site with a helluva webmaster and lost of content where you can, indeed, pick and choose whatever invented stat you want to support your point.