Re: Don't obsess over MPG, it's GPM that matters.
Exactly! Most people are clueless about math and need all the help they can get. When you buy an appliance there's a tag that says how much money it will cost to operate for a year (assuming average usages and electricity prices). That's what we need for cars. The MPG nomenclature hides the fact that there are diminishing returns to increasing efficiency. Try asking people the following question: Which would save more gas: modifying a 15 MPG minivan to get one more MPG, or modifying a 45 MPG compact car to get *10* more MPGs? Improving the minivan saves more gas, of course. Most people would get this wrong.