The Seahawks have done a much better job with their personnel since Pete Carroll took over three years ago, but there still is a gap between them and the Cowboys. In this game, Seattle needed to get some breaks, and thanks to problems on the Dallas special teams, the Seahawks were indeed able to get 10 points off turnovers.
There were two things that were going to help Seattle's rookie quarterback Russell Wilson against the Cowboys: his defense and the running game with Marshawn Lynch. The Seahawks plan was pretty simple in the first half. They relied heavily on Lynch and they didn't let Wilson make any critical errors. In the second half it was more of the same, with Lynch running the ball, which then protected Wilson from mistakes.
Where the Seahawks really hurt Dallas was in their ability to be more physical up front on both sides of the ball. The Cowboys really didn't have an answer for that all day.
Although the Cowboys offense was able to convert on third downs last week against the Giants, the Seahawks defense was able to hold them in check. There were opportunities to make some big plays early in the game, but Dallas was unable to connect. Dez Bryant and Jason Witten had some key drops that killed drives and the offense line didn't do a good enough job of giving quarterback Tony Romo the time he needed to make plays in the second half.
One of my biggest fears before this game was the lack of balance in the offense because of what I had seen the Seahawks do the week before rushing the passer. There were too many situations where long-yardage down and distances really allowed the Seahawks to dictate what they were going to do defensively. Seattle had a nice plan on both sides of the ball and was simply just better.