I could be wrong about this, but it seems like Chinander has it in his mind that for his 3-4 to be successful, he has to have these big 'tweener OLBs - guys that are in between the size of a "normal" OLB and a traditional defensive end. Nelson is sized roughly like that.
If you actually get a couple good starters that fit that build and are quick & athletic, you've hit the jackpot. But in my opinion those guys are just as hard to actually find & recruit as good traditional defensive ends; they're not just all over and I'm not convinced we actually have any of them at all on our roster right now.
I did a bunch of research last season along with a couple posts on here showing the size of Wisconsin's linebackers last year; they weren't big guys at all. And Wisconsin runs a 3-4.
I realize I can't like, keyboard warrior my way into a perfect take on all of this but what we really need at OLB are some athletes that fly to the ball, no matter how big they are or even whether or not they're particularly brutal tacklers.