Maybe you could try thinking that, as Nebraska fans, we have a first hand perspective on this and we're only telling you about Cos's incompetence as a public service. No matter, you'll eventually come to realize that he's a horrible coach.
Just to give you a brief preview here's what you have to look forward to with Cos as your DC:
1. Soft practices. During the season your defense will not conduct full speed tackling drills. Instead they'll start a "shuffling wrap up, no take down drill" which will have a trickle down effect and your defense will become incredibly soft and passive.
Because as Cos has been quoted many times in the press with regards to spread offenses...
2. Zero player development. Players will actually regress under his instruction.
3. Bloated, overweight, fat, slow players. He'll have your DE's upwards of 270-280 lbs, 250-260 lbs LB's.
Finally, you guys ranked 80th nationally in total defense in '08. I know, I looked it up.
http://web1.ncaa.org/mfb/natlRank.jsp?year=2008&div=B&rpt=IA_teamtotdef&site=org
The saddest part is that you guys will probably get WORSE on defense under Cos.
Do you want a little historical perspective?
Nebraska, under Cos, was:
2006---56th in total defense.
2005---26th " "
2004---56th " "
Wisconsin, under Cos, was:
2003---92nd in total defense.
2002---63rd " "
2001---58th " "
2000---79th " "
I would've gone back even further had the stats from the site I was using listed that information. The point here is that he's a horrible football coach and the statistics back up my claim.
Good luck guys.
Edit: Oh and one last thing...his players quit on him at Wisconsin, they quit on him in 2007 at Nebraska and eventually, they'll quit on him here.
Edit x 2: Look up Wisconsin's defensive stats AFTER Cos left, that would be 2004 and beyond, and you'll see a night and day difference.