My 5c worth:
The GO should go P1, but not drive dangerously. ie, why does he need to overtake a pumper on the way to the structure fire, when he could just sit behind them, and take command when they arrive? If the structure fire is so bad it needs to be upgraded, theres no saving the house anyway, so the extra 5 minutes won't really make a difference. And if the fire is only small, whats the GO going to do when he arrives? Try to blow it out?