Because Polamalu is a one-man wrecking machine.
If the play of one guy can be the reason for a team's second consecutive season of leading the league in scoring defense, the shining example would be Polamalu.
While he heard the calls of "overrated" in 2011, his importance in terms of run defense and his ability to alter passing attacks through his presence alone were critical to the Steelers' 2011 defense.
The real question with his four-year, $36.5 million extension was how long he'd be able to keep it up. That question still remains, but clearly, the Steelers are going to ride the horse until he bucks them off.
Performances like he had against St. Louis, for example, show that time has not yet come.
"For obvious reasons, we had some major leadership leave, people who we can count on, and I think it is nice for the young guys to see a familiar face," Polamalu told the Tribune-Review in May. "It is nice to be around the team and nice to get out and play some football. I am here to support all my teammates."
With three years left on that deal, the team will ask him to do a lot, in terms of both leadership and playmaking. While the Steelers defense was stout, the lack of turnovers forced plagued the team throughout the year. Under first-year secondary coach Carnell Lake, the Steelers pass defense was No. 1 in terms of yards against, but the defensive backs forced just nine interceptions - the team only had 11.
Clearly, it's something that will be emphasized in 2012, but interceptions are more the result of a defensive back being in the right spot at the right time, and is influenced by a pass rush, which also dropped off quite a bit from 2010 to 2011 (48 in 2010, 35 in 2011).