Oh man I can't believe how stupid people are sometimes. Every DE we've talked about drafting and using as an OLB is fast enough and athletic enough to cover, you can teach players like that to cover easily... especially since most of them have played in coverage during a zone blitz. So you bring up Hali who isn't fast enough or athletic enough and don't get why we can't use him?
You can teach someone athletic enough to cover a lot more easily than you can teach them to pass rush. Maybe in HS when they can plow throw anyone it might be easier to pass rush, but when you have to teach them the technique and moves its a lot harder.