LINCOLN, Neb. -- They can't be called pop quizzes because they happen every day.
When safety P.J. Smith and his fellow Nebraska defensive backs enter their meeting room each day, they know exactly what's coming.
"This is the first time we've ever taken tests," Smith told ESPN.com. "Since the season ended, we had a test every week. And now, since [defensive backs coach Terry Joseph] is here, we have a test every single day we get in the meeting room."
Joseph's exams typically contain three questions, which require short written responses. The players have two minutes to complete their choices, which is 119 seconds longer than they have during games in the fall. The players with the lowest grades at week's end typically have to clean the secondary room.
"He tries to put pressure on us," Smith said.
Pressure is one word to describe the theme of Nebraska's offseason, particularly on the defensive side. Details is another. So is accountability.
The team ended the 2011 season with a thud, falling 30-13 to South Carolina in the Capital One Bowl. A defense that had entered the fall with a star-studded lineup -- tackle Jared Crick, linebacker Lavonte David and cornerback Alfonzo Dennard were the headliners -- finished 42nd nationally in points allowed and 37th in yards allowed, significant drops in both categories from the previous season (ninth in points allowed, 11th in yards allowed). The Huskers' D received some A-level performances from David and Dennard, but the overall unit, aside from a few exceptions, wasn't exceptional.
Nebraska didn't generate enough pressure (84th in sacks, 112th in tackles for loss) and didn't really have a hallmark.
"Generally, we didn't make a ton of busts a year ago," said defensive coordinator John Papuchis, who coached the defensive line in 2011. "But it's the small details within each defense that make the difference between being a good defense and a great defense. At times, we showed signs of being a very good defense. And at other times, we didn't live up to the standard we have set for ourselves.
"And I think what held us back more than anything came into those details."
Papuchis and the other defensive assistants have spent the offseason stressing concepts rather than pure memorization. The how and the why became more important than the what and the who.
They "went back to square one," even with older players, and worked on terminology as an entire unit. Crick and other Nebraska players talked before last season about the uniqueness of their defense, how the scheme would help set the Huskers apart in a new league.
"There's not one defense that’s comparable to ours," Crick said. "Very complex, and that's what makes it unique. As a defensive lineman, I have five responsibilities, where other defensive linemen, all they've got to do is shoot their gap. We want it that way."
And it is different, as Nebraska uses a two-gap system not employed by most college teams. But because of several reasons -- the coaches point mainly to attention to detail -- the Huskers didn't enjoy a major schematic advantage.
"Our defense is kind of like learning how to study math," Papuchis said. "If you don't have a foundation, everything else after that won't make sense."
One issue Papuchis noticed with Nebraska's youngish secondary in 2011 was alignment. Players knew their responsibilities, but they would line up inside when they needed to be outside, or vice versa.
"What doesn't seem like a big deal, six inches one way or the other, makes all the difference in the world if they convert third-and-6," he said.
It's why Joseph tests them every day. Mistakes happen, Smith said, but Joseph wants the DBs to "make a new mistake. Don't make the same mistake."
Nebraska should have a more seasoned secondary in 2012, and Papuchis has been pleased this spring with Daimion Stafford, Ciante Evans, Andrew Green and Antonio Bell, among others. Linebacker Will Compton said the secondary is receiving extra attention this spring from both Papuchis and head coach Bo Pelini.
"We're getting back to some of the multiplicity we've had in the past," Pelini said. "I'm excited. I think we have a chance to be pretty good on defense."
There are different challenges for the other two groups on defense. The linebackers begin life without David, one of the nation's most productive defenders the past two seasons. Compton will lead the group, but depth is still a concern and will be for the next few years.
"We'll have guys very capable," Compton said. "It's about being a successful Will linebacker, not about being the next Lavonte David."
Nebraska has good depth at defensive end with Cameron Meredith, Jason Ankrah, Eric Martin and Joe Carter. And while the scheme stresses the need to prevent offensive linemen from reaching the second level, pass rushers could be turned loose more as Nebraska tries to generate more pressure.
New line coach Rick Kaczenski has brought an attacking style.
"Last year, we were a little bit passive," Meredith said. "Now offensive linemen at practice are telling us, 'You guys attack a lot more.'"
The linemen also are stressing accountability. If anyone is late for a meeting or another activity, the whole group runs or does Turkish get-ups.
"Everybody had a sour taste in how we finished up the season," Pelini said. "I said, 'Either you can talk about it or do something about it.' I think everybody around here has taken the attitude to raise their level of accountability.
"To get over the top, we've got to have a little bit more attention to detail, raise our standards that much more, raise our accountability that much more."