Sorry that my radical views of 21st century outside linebacker speed defense is causing so much dissension in the ranks. All I can say to the speed/coverage vs mass/immovability argument is that the offenses are becoming "spread" [whether running oriented a la Oregon, or passing oriented like Holgerson at WVU]. That means mass/immovability against the average future team is going to be checkpoint two on the list rather than checkpoint one. Sure, against Wisconsin, or more real MSU and the old Pitt [note that the former Tulsa coach is re-doing Pitt, though], put Carlo Calabreese in there, but the other teams are going to stress you in space both short and deep. Passing spreads are going to go at you in the 8-12 yard area --- linebacker country. Scrambling QBs are going to ask your LBs to close a lot of ground. If you cannot both run fast AND have flexible direction-changing hips [just like the DBs], you are never going to be there to deliver the "mass" to the opponent.
I fulminate unconvincingly I know, but I have watched my brother's team, VT, play this way for over a decade. Last year's WVU team was the same way. "Southern Speed" became a legend when way back when FSU and Miami brought in smaller, super-athletic, speed linebackers to chase everything down everywhere. Even the Dallas Cowboys broke the line in one phase of NFL football back then with speed linebackers [the only reason that you don't see this as obviously in the NFL today is because they can find the freaks who are both big and fast in this age.]
This is why I wanted Perkins so badly...big enough, VERY intense about hitting people, fast, and demonstrated great coverage skills at the 7x7s. That's why, when I saw us limping along at OLB coverage candidates, I floated the idea of a smart, fast, coverage convert named Nicky Baratti. It's all bs imagination by me, but from my distance, he fits the design of the cover-the-space OLB. Badger would too, but the thought of him going downhill Zibbyknockering the opponents is too much not to want to see it from safety.