Jon Rutherford,
Two quick points:
1) The introduction of the 55 mile-per-hour limit resulted in the very well documented decrease in traffic fatalities;
2) I used to travel roughly 25 minutes on the freeway at speed limit on a regular basis. Upon attempting to decrease my arrival time by increasing my speed by 10 miles per hour, I saved a few minutes.
3) On my bike, in an hour-long ride to work, a one mile per hour increase in average speed saves about the same amount of time.
4) Did I say two quick points?
:blush: