LifeInSepia
Right, if the scrum half takes a quick tap from the die line, or its a penalty, then the scrum half passes it back to the fly half, who draws the opposing man over to the right of the scrum half, and then the fly half passes it back to the scrum half. This would create masses of space for the scrum half to run through, depending on the wit of the opposing centers. The forwards could shield the SH as he runs through.