In Reply to: Slammin' on the brakes posted by Long Distance on October 07, 1999 at 10:05:45:
The two second rule would work only if the car ahead could somehow come to a dead stop instantaneously. It cannot uless a concrete wall appears magically on the highway, and hopefully you would see that coming. The closing rate is always going to be the difference in velocities between the two cars. If he hist the brakes hard and goes from 60 to 40 in 2 seconds (for example) and you are following at 70 with a 2 second delay, and you somehow do not react for those two seconds, he will have averaged 50 (roughly) and you 70, your closing rate is still only 20mph (not huge) and you still have a long time to apply brakes. Trust me, I've seen it in action, and it works.