Well, when you put it that way, I don't disagree, especially if it's a general observation.  I don't even know what the term means!  Total yardage per game?  TDs?  Scoring?  Guys like Al Michaels constantly use this phrase, and as far as I know, they've never defined it. 

Just for grins, I looked it up.  Total yards per game (DEF) top 3 are Pitt, Jags, Cincy.  Points per game top 3 are Seattle, Jags, Pitt.  Pass DEF is Denver, Pitt, Carolina.  Rush DEF is Eagles, Denver, Vikings.  That was actually sort of interesting!