This is one area where I have to disagree. Other than DB's, more specifically CB's where the "rookie rule" applies, stud talent reigns supreme. Guys like Revis and Asomugha who are the rare "shutdown" type corner and the rare exception, the most talented IDP's are the guys that typically score the most, scheme permitting, especially regarding LB's and DL's. DB's tend to be a crap shoot from year to year but there are plenty of guys who perform well year to year and not because they are on the crappier half of the talent spectrum. They are the ones who play all 3 downs and who are the foundation of their defense. In every IDP league I play in a top LB can score almost as much as a top WR / RB. I agree that it does take a bit more time to keep up with but if the scoring / lineup requirements are designed well it takes playing FF to a whole other level IMO. I could never imagine playing with a TEAM DEF again, but it's probably an acquired taste for sure.
ETA - Actually after looking at Revis' final scoring in several of my leagues he was the #8 CB overall and the #28 DB overall.