I don't agree with this.
The biggest difference was coverage. Take a look at the first and second half of the SB. Before and after Shields and Woodson went down.
We were DOMINATING the Steelers completely. Then we're forced to play a lot of zone in the second with secondary scrubs, and we almost lose the game.
Of course the pass rush improved tremenduously, specially the inside pressure that I so clamored last year. Raji and Jenkins made things a lot easier when the secondary wasn't as stout. And CM3 is CM3.
Also, being in the second year in the scheme, it's much easier for the players, they can play a lot faster.
There's also the ILB position. Hawk was a much better communicator than Barnett, Bishop was a clear improvement over both, and with Chillar on the IR, we didn't have as much coverage breakdowns as we used to.
But if I had to single out one reason for the improved sucess, it's the secondary. Tramon elevating to shutdown corner status and Sam Shields playing so well and being so fast, it made all the difference. We could take away a receiver without having to shift coverage nor double team, our nickel corner was as good as any slot receiver, it allowed Woodson to be used as a rover, and create wravoc everywhere.