got this off cbssportsline, from whoever writes the "rapidreports" for each game. had never really thought about this.
49ers FB Moran Norris = offensive death. They put him in for his first snap of the game on a second and 7, and, predictably, RB Frank Gore got stuffed for no gain. A three-and-out for the Niners is almost a certainty whenever Norris sees the field.