Yal:
In what concerns your observation about reducing the auto wheight, I'm taking measures now: my wife will never again be allowed to seat in the car while driving
Actually after your observation I was curious about quantifying the effect of driving arround with your wife on the braking distance. A quick calculation revealed me that a 5% change in the total weight of the car could actually make a difference of more than 10 meters if your are bringing the car from 100 Mph to a complete stop. Wifes out of the cars?:p