Understand what you are saying but disagree .. Only two of the six games have been "out-of-hand". So that does not explain the offensive output!
In all but Colorado and Northwestern, Nebraska was down by at least 17 points late in the first half or at halftime. So while the final outcomes may not have been out of hand, the offensive production came after teams had gotten out to fairly substantial leads.
Do we think Northwestern's offense was great the last 3 minutes of the game or was the defense playing poorly and perhaps a little overconfident.
Again, I am not saying there hasn't been any improvement, just that the offense starts slow, the team gets behind, the offense does better in the 2nd half, against teams with bigger leads.
Looks like this
1st half - offense struggles, defense on the field a lot, defense wears down a bit, opponents score
2nd half - offense has more success, defense not on the field as much, defense holds opponents to less points, score looks respectable in the end.