It's all about the pass rush.
In my opinion there is nothing that special about either team's secondary. Josh Norman is good but even your best secondary players in the league can get burnt without a pass rush. A good pass rush creates turnovers and produces pro bowl caliber secondary players.
I don't think it's all about the pass rush. I think it starts with the secondary. QB's get rid of the ball so quickly that often times the pass rush can't get there even if a pass rusher went completely unblocked.
The first step starts with tackling. Every single team I've seen in the playoffs tackles better than Dallas. Especially in their secondary. And most of the teams were substantially better tackling teams than Dallas.
The ball is getting out of the QB's hands quickly and into the hands of a playmaker in the open field. You have to bring down the ball carrier immediately and make those passes ineffective.
You need safeties and corners that can play both man and zone so the defense can switch up man and zone and be able to face the wide variety of pass patterns from different teams. Dallas didn't play much zone and got killed on pick plays. When they played zone, corners like Claiborne and Carr were not all that effective in part because they were terrible tacklers. Wilcox is horrendous in zone. So now you become a clear as day defense where the QB knows what the coverage is and knows where to go with the ball. And that means less INT's and less sacks.
So the pass rush is a moot point if you can't switch up and disguise coverages. And you're going to be attacked with short passes if you struggle to tackle well.
For me, I would rather fix the coverage issues on the backend first and then worry about the pass rush. This isn't 1995 anymore. Hell, it's not 2005 anymore. Pass rushes can now be rendered moot.
YR