I would like to say I would have said D but if I was completely honest probably F.
Our schemes were just terrible. I was at the BYU game and I could tell in the first half that Banker's defense wasn't going to work. And, while Langs passing game was OK it was obvious that he had no clue how to develop a running game.
Since I'm sure you're wanting me to compare to this year, the schemes we are putting into place are significantly better. I've thought this offense would be a perfect fit for Nebraska since Chip Kelly was running it at Oregon - long before Frost was on the radar as a possible head coach. It lessens the need for elite offensive linemen, allows you to take guys who are athletes and let them make plays and avoids having to compete with the USCs, Notre Dames, Miamis, Alabamas, Florida States, etc for top-shelf pro-style QBs (though some of those have also moved away from that over the years). Langs just had no feel for play-calling and barely cared about the running game. On a yards per play basis, Langs was basically even with our offense from the year before (slightly down but close). He got worse from there but that wouldn't affect the 2015 grade. On the other hand, Frost got us 0.72 YPP better than the previous year which moved us up 42 spots in the national rankings. And that was using most all the same guys Langs had the year before - except for QB but Langs was supposed to have "his" QB last year too.
And, like I said, it was obvious that Banker's defense was bad. He took a team with Chris Jones, Maliek Collins, Vincent Valentine, Josh Banderas, and Nathan Gerry - all of whom got at least a decent look in the NFL - and turned it into the #92 defense in the country (YPP) while facing one of the worst set of offensive opponents we've seen in the last 10 years. I don't know if the current defense/coordinator is the answer but Banker made us 0.75 yards per play worse than the year before he got here. Chinander got 0.64 yards better than the year before.