It's not TO that will make the difference against Pittsburgh, it's Brian Westbrook who was out in the loss to the Steelers earlier this year.
The loss forced the Eagles to change their defense and put J. Trotter back in the middle. Once they did that, the Eagles were much improved against the run.
If Philly can run on Pittsburgh enough to keep their defense honest, they'll outscore the Steelers, whether they have TO or not.