[Balding_Eagle]

Increasing speed from 25 to 40 nearly doubles the distance need to stop from 85 ft to 164 feet.

Increasing speed from 55 to 70 only increases the distance need to stop 46% instead of 93%, from 265 ft to 388 feet.

http://www.csgnetwork.com/stopdistinfo.html

[SoldierDad]

And you believe that those percentages are the most important yardstick of measurement with respect to this issue? You should really re-read what you posted and ask yourself why you think this is important.