Thing is great defenses are built on the back end too. It's fine to bounce matchups with front seven vs OL and it will provide good insight, but if you look at playoff history there is a direct correlation between winning it all and scoring defense. However they do it, some teams are great at keeping others out of the endzone and that provides an enormous advantage.
Looking at this weekend I expect Green Bay and Seattle to advance. In that scenario Green Bay goes to Dallas, while Seattle goes to Atlanta. Of those matchups, if it goes down that way, I actually think Seattle might upset Atlanta. But I don't think Green Bay will knock off the Cowboys.
Both the Cowboys and Patriots are interesting because they're not just strong scoring defenses, but they also have potent offenses. Outstanding balance, and of the two I think the Cowboys have the smoothest chance to get to the Super Bowl because no team in the NFC really can compare. Patriots, meanwhile have the best scoring defense in the league but also of course that strong offense, however they do have a very good team in KC who might be ready to give them a run for their money.
All that said, can't wait to see how wrong I am. I don't bet on playoff games for that reason lol.