The referee said that you hit Brian Sipe too hard. Did you hit him too hard?
I hit him as hard as I could - Jack Lambert
At some point in the 2011 season, Wallace lost his heart for playing in Pittsburgh. He still had the speed, and that can do a lot, but without heart you don't get as much as you should out of him, and you also get your share of negatives.
The problem is how that situation arose. The Steelers could have kept him happy, and would likely have had a much different version of 2012 Wallace as a result. And likely, a 2013,14,15...
Schiavone's Race Career: