How much of this is a flaw and how much is is that most QBs are Right handed and it's much easier for them to throw the ball moving to their right than to their left? By doing so, you open yourself up to being sacked by the left side of the defense....
It may not be that simple I know, but just saying this could be the problem as well. In playing the demo, I notice that even a little bit of pressure from the right side and the QB moves to his right a little bit..