Our OL made a lot of RBs look better than they were. Conversely, guys like Abdullah made our OL better than they were.
Spot on. Any review of a '80's or '90's Nebraska football game and you'll see running backs routinely make it at least to linebacker level before first contact. Five plus yards before you're even touched makes being a successful running back a whole lot easier. Abdullah (and Burkhead as was also mentioned) had to make sometimes spectacular plays to gain a yard, frequently having first contact well behind the line of scrimmage and often coinciding with being handed the ball.
I'm having a hard time not equating overall running back success with line play.