Steelers had 14 drives, which is a little higher than usual. One was a kneel down, one play drive at the end of the first half, and one was a desperation drive against a prevent defense at the end of the game after the game was no longer in any doubt.
So, 31 points in 12 real drives, and 440 yards (taking away the yards gained on the final drive; you can't count the yardage if you don't count the drive). That's more than 2.5 points per real drive and nearly 37 yards per real drive. Those numbers are pretty high for a home game -- and they're very high when you consider the Steelers had only scored 17.9 points per game coming into this one. 6.6 yards per play is high too.
It's not a recipe for long-term success -- it's especially interesting that the Patriots were ok at third and fourth down conversions, holding the Steelers to 6-15 on third and fourth down conversions (again taking out that last drive). That means the Steelers were getting very big chunks on first and second down.
Like everyone else, I chalk it up largely to injuries -- especially Talib. The team did well enough to win, and I think that's the real story of the game. Trying to make too much out of 31 points misses the correct story, IMHO. The one nugget from the box score, though, that's a bit of a concern, is how well the Steelers spread the passing game around. Four receivers with better than 65 yards and five with better than 43 yards, and that's despite the fact that the Patriots were getting decent pressure. That's a bit of a concern.