As some have suggested here, Pelini is a competent coach but is a hot head and speaks before thinking.
I don't think our current AD would seriously consider him. Barnhart is not competitive and wants no challenges.
Allegedly, Pelini said the following (according to Wikipedia):
First Audio tape leak
Following a home game loss to
UCLA Bruins on September 14, 2013, and shortly after responding to criticism from former Nebraska football player
Tommie Frazier about the loss, a two-year-old audio tape with a profane tirade by Pelini was anonymously leaked to
Deadspin. The recording was made following Nebraska's come-from-behind win against Ohio State in 2011, when it was reported that some students left when Nebraska was down 27-6 early in the 3rd quarter. The Huskers won 34-27. According to Deadspin, among the statements made on the audio recording, Pelini said:
"Our crowd. What a bunch of ******* fair-weather f***ing—they can all kiss my @$$ out the ******* door. 'Cause the day is f***ing coming now. We'll see what they can do when I'm f***ing so f***ing pissed off."
Second Audio tape leak
Following his firing on November 30th, 2014 Pelini met with his (former) team at a
local high school on December 2nd. Leaked audio of the meeting revealed that the coach verbally attacked University of Nebraska administration. At one point Pelini said:
"It wasn't a surprise to me. It really wasn't. I didn't really have any relationship with the AD. The guy — you guys saw him (Sunday) — the guy's a total p----. I mean, he is. He's a total c---."
https://en.wikipedia.org/wiki/Bo_Pelini