I'm glad to see this website and to see a small group of politicians supporting reduced speed limits.
I drive a reverse commute, I live in the city and work in the suburbs. About 2 months ago I started taking the "scenic" route to and from work. Instead of the interstate I take the side streets and country roads where the top speeds range from 40 to 55. I mainly made the change because it's a prettier more relaxing drive.
The trip takes on average only 10 minutes longer but the difference in fuel economy was amazing even when I knew it would make a difference. My Millenium Bug (2000 Beetle) went from averaging 30MPG to averaging 35MPG. My '02 MR2 went from 35MPG to almost 40MPG and my '04 BMW R1150R is getting 59MPG. And a third of the trip has stoplights!
It has never ceased to amaze me how many people seriously believe speed does not affect gas mileage.
The explanation I always use is this. Stick your hand out the window at 55MPH and then at 75MPH. Compare how much harder it is to hold it straight in the wind. That's how much harder the engine in your car is having to work.
I fully support a return to a national 55MPH speed limit. We've become a nation in a perpetual hurry. Slowing down a little, not just on the freeways will do us a lot of good.