LANDOVER, Md. -- Regular readers know I have this theory that Washington Redskins defensive coordinator Jim Haslett has been devising completely new schemes every week -- sometimes every half -- to overcome the team's injury and personnel issues on defense, and that the extent to which the players are buying into the ever-changing schemes is part of the reason for the team's success. After Sunday night's division-clinching victory over the Dallas Cowboys, I ran my theory past Redskins nose tackle Barry Cofield, who said I was right.

"A great defensive coordinator is kind of a mad scientist," Cofield said. "And I think guys are energized when they come to work every Wednesday thinking, 'What's he got for us this week?' I think you definitely see that."

The Redskins finished the season ranked 28th in the NFL in total defense, allowing more yards than every team but the Buccaneers, Jaguars, Giants and Saints. But somehow, that didn't sink them the way it did those other teams.

"We're good enough, right?" Cofield said. "Good enough to get to the playoffs. Good enough to win seven games in a row. We definitely want to play better. We hear 'bend, don't break,' but we don't want to bend or break. But we've been good enough to win."

Sunday's fresh new plan was a blitz-heavy scheme that saw the Redskins confuse and pressure Cowboys quarterback Tony Romo into three interceptions. There was nothing on any 2012 Redskins film to make Romo or the Cowboys believe they'd see London Fletcher blitzing inside, Rob Jackson blitzing outside and Cofield basically trying to occupy blockers and clear room. That wasn't the way the Redskins played defense this year, but it was the way they practiced it all last week because they wanted to show Romo something different.

"Defensively, we did something that we haven't done, and we thought we'd have a chance to keep them a little off-balance," head coach Mike Shanahan said. "If Tony knows what you're going to do, he's going to tear you apart."

Haslett and Shanahan flat out-coached the Cowboys' Jason Garrett, who was unable to make the adjustments in-game to the Redskins' blitzes. But part of the reason it worked was the surprising ability of cornerback DeAngelo Hall to handle red-hot Cowboys wide receiver Dez Bryant before Bryant had to leave the game with back spasms.

"Dez has been on a tear these last couple of weeks," Hall said. "I knew they were going to put me out there with him and I was going to have to play my best game."

Which he did, and the big guys up front kept Romo so flustered that he never adjusted away from those low-percentage sideline routes to screen plays or to Jason Witten over the middle.

"Still comes down to execution," Cofield said. "But it's a beautiful thing when it works."

So what do they have in store in this week's playoff game for the Seattle Seahawks, who scored 150 points in a three-week stretch from Weeks 14-16 before coming back to beat the Rams 20-13 on Sunday?

"We'll find out Wednesday," Cofield said. "It was good to see them look human today for a change, like a normal team that has to fight like everybody else."

The Seahawks present a fresh challenge for the Redskins -- one that demands a fresh look. Anybody who's been following this Redskins defense for the past couple of months knows to expect the unexpected.