If you're in a base defense, or even nickel where you need an outside linebacker in coverage, you are basically asking for calamity if you fail to use your OLB with the best coverage skills.
If you move him up to the LOS, as a DE, you're basically weakening two positions. Nebraska will utilize Alex Davis as a pass rusher with the #1's in clear cut 3rd and long Nickel and Dime situations.
A lot of people are really concerned about the pass rush, and I think its viable, but I also know Nebraska will present a very diverse and multiple schematic look this year on defense. I've even heard the potential of a 3-2-6 look vs. Spread teams. They will be doing a lot of things to help manufacture pressure on the QB.
3-4 BABY!