I am sure it is drilled to these RB's but it seems like the players that do this scrambling are imagining a 3 foot bubble around the defender that if they enter that bubble, they will get tackled.
Have you seen the tackling out there?
The best RB's that seem to hit the hole and fly are always brushing past arm tackles and whiffs. Run at 'em and then brush past them!
Vidor seemed to always have kids that ran at the defense. If you were a bad tackling team, they could run all over you.