Do I detect a hint of sarcasm?
In Chi-town, on a 4 lane wide road, from right to left it works like this. 55,65,75,85+. Trucks are confined to the two right lanes. But you will see trucks AND cars doing 75-85+ in ALL the lanes.
My point is this. What's more dangerous. A truck doing 75 who slams on his brakes or a car doing 75 who slams on his brakes. Most people will say the truck. That's why when referring to the speeding issue in this thread, the emphasis is on trucks speeding not cars (as your post followed suit)
But think carefully about the scenario. What happens when that truck slams his brakes and what happens when that car slams his brakes.
The truck, if he stays straight, will come to a screechng halt in about 100-200 yrds. If his trailer rear swings out and jack-knifes, he will stop in a shorter distance due to the extra resistance. If the speed at the time of jack-knife is still pretty fast he may flip thus providing more resistance.
If a car going that fast slams on the brakes and stays straight, not a big deal. 50-100 yrds maybe? But since cars are lighter and more suceptable to the airflow under and around the car, very rarely will they stay straight. They will have a greater chance to flip AND THEN GO AIRBORN! OUCH!