I admit I have not done extensive analysis of this but after watching the Seahawks game a couple of times focusing on the run game, I am wondering if the problem is more than just the OL not creating any holes to run through. There were several plays I saw designed to go to the left, but it looked like room opened up on the right. Pollard and Rico just ran into the pile when they could have cut back to the left where there was more room. I am not say they would go for 40 yards, but they could have gotten 5 instead of 0 or -1.
Again, I am not saying this is the only problem with the run game. There are more. Terence Steele when he pulls to his left, instead of driving into the hole and blowing out the DE or DT, he kind of throws a soft block and gets no movement. The guy who pulls has to come with great force and momentum and drive the defenders out of the hole. A 300 lb lineman running full speed bring a lot of force but Steele seems to soften the blow instead of bulldozing his way into the hole. When I played OL in high school if I pulled like that my coach would have kicked me in the pants then made me run laps until my feet bled.
Then, and I am not sure is this was by design, I saw a couple of plays where Luepke at FB drove into the right side of the line and Pollard went left. Not sure why he didn't follow the FB. On one play there was a hole where Luepke ran into but Pollard went in the opposite direction as soon as he took the snap and he got tackled for a loss. I love running behind a FB but the RB has to get behind the FB and use him as interference. Again I am not talking about getting an extra 20 or 30 yards, but perhaps the difference is 7 yards instead of 0. And btw, Luepke is not a great blocking FB in the run game. He does okay but he does not hold his blocks very long.
At the same time it is hard to complain about the offense when they march up and down the field at will. Still, in the red zone it would be good to have a decent running game to keep the defense honest at least.