[pstrbrc]

I'd just like to point out a couple of things.
#1. Utah is (last I checked) in the Good Ol' U. S. of A., where (at least for a short time longer) "personal freedom" is considered a primary national virtue. Now, I have to admit that when a fully loaded F-350 Crew Cab with ladders and other paraphernalia strapped to a top rack barrels past me going at least 10 mph faster than my 70 mph (at which I'm getting 37mpg, which, with my wife in the car, calculates out to 72person-mpg), I wonder. I presume he knows what kind of mileage he's getting, and he's run a cost/benefit analysis in his head, and he's comfortable with the cost. The fact that I'm a cheap Scotsman and he's the Prodigal Son is an individual choice for each of us.
#2. Last I heard, cows produce more "greenhouse gas" than just about anything else on the earth except volcanoes. I'm still eating beef. I guess somebody who chooses to burn petroleum faster than me isn't any more evil.
#3. Everybody going 70 on a metropolitan interstate is more dangerous than everybody going 60. however, raising the speed limit on said metropolitan interstate to 70 won't make everybody go 70, 'cause that's just too fast for some people (and some cars!) so the danger level increases. BUT... Utah is not known for its densely populated metro areas. It's known for long straight empty stretches of highway. When 55 was the "national" speed limit, those of us who drive those long empty straight highways almost died of boredom. 65 was survivable, and 75 is pretty darn nice. And, no, it's not remotely "dangerous". Now, somebody living in western Massachusetts might not get this, but a 300 mile trip one way is fairly common out here on the Plains, and there is no other choice but the car. For me, the difference between 60mph and 70 mph is 2.2 gallons versus 1.5 hours. And when that 600 mile round trip has to be done in one day, that hour and a half less driving is very much a big safety factor.
so, in a nut shell, until you've driven a week in my car, get over yourself.