  Mitt Romney has come out strongly against the Obama
administration's newest fuel efficiency standards for cars and
trucks—rules his campaign calls " extreme."  The Republican
presidential nominee says that if he takes office next year,
he'll consider rolling back the fuel standards, which require
car manufacturers to make drastically cleaner and more efficient
cars over time.  In June, Romney told The Detroit News that he'd
seek "a better way of encouraging fuel economy" than the
Corporate Average Fuel Economy (CAFE) requirements. A campaign
spokesperson recently reiterated Romney's opposition, saying
that any savings consumers see from CAFE at the pump "will be
wiped out by having to pay thousands of dollars more upfront for
unproven technology that they may not even want."  But changing
the new vehicle rules is easier said than done, according to
clean-car and auto experts interviewed by InsideClimate News.
While Romney could indeed water down or severely limit the
standards, he'd face so many hurdles tha