FB Korey Hall missed last week at Jacksonville, and might miss the Monday night game at Chicago. It seems to me that the Packers, specifically RB Ryan Grant, run the ball better when Hall is the blocking back instead of FB John Kuhn.
Here are Grant's stats in 10 games that Hall played:
Here they are in 5 games that Hall started:
And finally, here they are in 4 games that Hall didn't play:
And in conclusion; it doesn't seem that he has made a difference. There hasn't been any pattern in Grant's games this season. He was lousy against poor run defenses like Detroit, Indianapolis, Seattle, and Jacksonville. But he's great against good run defenses like Minnesota, Chicago, and Tennessee. That isn't a pattern either because he struggled against tough run defenses like Tampa Bay and was great against Houston's lousy run defense.