but is there no significance in the fact that the other car is pushing INTO your car rather than just being stationary as say hitting a brick wall would be??
I would have thought that if you hit a wall, the total force exerted back through the car would be less than hitting another car coming your way at the same speed which would be exerting force of it's own back in your direction and hence increasing the amount of total force being exerted back into you car??
p.s. I hope you know what I mean because I'm no tech... hehe