After owing 4 gas trucks / suvs and then 2 diesel grand cherokees I can't agree more. EPA #s are a joke as they are done in a lab on a dyno and more often then not the vehicle was never actually tested but an algorithm was used to calculate EPA mileage. WSJ is finding (finally) that this practice is misleading customers who can't get EPA even when trying to whereas diesels we are finding that we get EPA on average and better.
"The EPA currently requires a five-part lab test that simulates driving under conditions that are repeatable from one car to another. Because of the number of vehicles on the road, the agency runs tests on only about 15% of the industry's models each year to check the accuracy of mileage claims.
In real world use, hybrids for many auto makers tended to underperform the lab results. Meanwhile, diesel engines tend to perform much better than the label—by almost 5 miles a gallon, according to The Journal's analysis. The spread is so significant that Mr. Grundler has asked engineers to look into why the testing of diesels doesn't reflect real-world results more closely."
Link to article but requires subscription: EPA Wants MPG Claims Road Tested - WSJ