So the conversation in the lawyer/engineer post about the new CAFE standards turned, as it always does, to people's fond reminiscences of high-mileage cars of days gone by.
The most recent time that America really had mileage on the brain was in the wake of the '79 Energy Crisis. If you go up to my attic and look at car magazines from the era and I can talk you out of offing yourself, you will notice that nowhere in any of the auto ads of the period are things like horsepower or acceleration touted at all. Everything is Em-Pee-Gee: Even the ads for the brand-new Camaro touted the mileage you could get from the base Iron Duke four-cylinder powerplant (and I use the term loosely) and conveniently forgot to mention that a four-banger Camaro wouldn't accelerate hard enough to pull a greased string out of a cat's ass and would get sand kicked in its face at traffic lights by any passing Beetle.
The early '80s saw plenty of cars that would be considered efficient even by today's standards enjoy sales success in America, from the Toyota Starlet to the Honda CRX HF, which sometimes leads people to ask "Well why don't they just sell those cars again?"
Because they wouldn't be legal to sell. They lack airbags. They'd fail side-impact and offset crash tests. And, more importantly, have you looked inside a small car lately? All but the most wretched clean-it-out-with-hose loss leaders on your neighborhood dealer's lots are stuffed full of things that used to be considered amenities: power windows, remote adjustable mirrors, power door locks with remote. Automatic transmissions outnumber manuals in passenger cars by a staggering margin, and even performance-oriented cars are like as not to have some paddle-shifted clutchless setup rather than the classic three-pedal row-your-own.
The aforementioned Toyota Starlet, one of which was my dad's commuter vehicle for many years, was a two-door hatchback on a tiny sub-92" wheelbase that weighed in at under 1700lbs; by comparison, a current Prius stretches over 106" between the axles and weighs in at over 3,000 pounds. (And lest you think that's all batteries, even the current Mini outweighs a Starlet by better than 700 pounds despite being a good ten inches shorter.)
I don't mind austere cars that crumple like beer cans in a wreck, but the rest of the market seems to think differently...
(Eurodiesels get good mileage these days even in lardy modern autos, but try telling that to the EPA.)