The excuse is simple.
A season later, the reality -- specifically on defense -- is simple, too.
"These guys have a lot of pride and they want to make sure we're carrying our share of the load," Capers said.
The Packers flirted seriously with perfection during the 2011 regular season, only to get knocked out in their first playoff game. Green Bay also ranked dead last in total defense. It's a mark the unit doesn't wear well, but also one it doesn't overly stress, because scoring defense, takeaways and, somewhat oddly, quarterback rating are the points of emphasis.
No specific points are being emphasized more, though, than fixing the pass rush, improving pass coverage and tackling better.
The defense's ability to perform in those areas took a major blow when underappreciated inside linebacker Desmond Bishop suffered what was likely a season-ending hamstring injury in the Packers' preseason opener against the San Diego Chargers. Bishop's versatile skill set -- he can stuff the run, jack-hammer tight ends at the line of scrimmage and play well in pass coverage -- allowed the Packers to do certain things that now must be re-imagined. D.J. Smith will take over for Bishop; while Smith's impact will be different, Capers is confident there won't be a drop-off.
"D.J. also is a three-down player, so we won't have to change a lot. But you have to have enough in your package so if lose a guy, you have enough there that you don't start over again," Capers said, meaning there are other options within the overall scheme to play to individual strengths.
One tweak will be using outside linebacker Clay Matthews occasionally at inside linebacker. Matthews, one of the league's top pass rushers, already had moved from left outside linebacker to the right side. This should help with the pass rush (Matthews will be playing on the blind side of right-handed quarterbacks) and allows first-round draft pick Nick Perry to play a more natural role at left outside linebacker.
"We moved him back to the right side, but you'll see Clay playing all the [linebacker] spots," Capers said.
Charles Woodson has shifted positions, too, from cornerback to safety. Green Bay wanted to add smarts and instincts to a position that suffered in 2011 after Pro Bowl safety Nick Collins sustained a neck injury that still has him out of the game. Woodson and fellow safety Morgan Burnett will combine to make play calls, Capers said, and Woodson will play against slot receivers in nickel sets. Having Bishop on the field would have given Woodson more freedom as the nickel defender, because Bishop was able to disrupt slot receivers and tight ends. Smith is capable of doing some of the same things, but Woodson might have to bear more individual responsibility now.
Woodson's shift left veteran Jarrett Bush and Davon House -- a talented second-year player who is liked by the coaching staff -- vying for the starting cornerback job opposite Tramon Williams. House, however, was also hurt in the Chargers game, sustaining a shoulder injury that could sideline him for most of the rest of the preseason.
The personnel changes were driven by circumstance. How the unit executes in a strong, pass-happy NFC North could determine whether Green Bay delivers on high expectations. One key will be simply handing the ball over to Aaron Rodgers and the Packers' explosive offense. Under Capers, Green Bay has routinely been among the NFL's leaders in takeaways. The Packers' 31 interceptions in 2011 were easily the most in the league. (The New England Patriots and San Francisco 49ers tied for second with 23.)
"With our offense, if we can be disruptive, we've got the right combination to win," Capers said. "When we've been tough on opposing quarterbacks, we've won around here, because we've got an excellent quarterback."
Capers said years of study have proven that winning NFL teams tend to have a favorable quarterback-rating differential in games. Last season, Rodgers' huge weekly ratings dwarfed the lower ratings by opposing quarterbacks, a disparity that was reflected in the Packers' 15-1 record. Green Bay held opposing quarterbacks to a rating of 87 or less 11 times -- all victories. The Packers allowed opposing quarterbacks to rate above 100 four times, but in two of those games, Rodgers exceeded his counterpart's rating by more than 20 points.
"The past three years, we're 40-14," Capers said of Green Bay's regular-season and postseason record. "Of those 54 games, 34 times, the opposing quarterback rating was under 80. We won 32 of those 34. Our differential is usually over 40. That's the way the game is played nowadays."
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