I do not disagree about the absolute neccessity of a good Oline to consistently run and throw the ball, but, we're talking about the "anatomy" of this one particular play. I'm not seeing it the same way you do I guess. If the Seattle Oline completed their assignment, one would think that there was an opening to run through. Watch it again. There was no opening to run through. Lynch ran into a brick wall, bounced once, then busted through that brick wall. Then he just made the rest of the defense look silly.