From what I've read, the EPA hasn't changed its testing procedures. The EPA is just revising the published numbers by taking their test numbers and reducing them to reflect "higher speeds" and "increased A/C use". This isn't the first time they've done this, though: the EPA did the same thing in 1984, and now they're doing it again, probably because the 1984 reductions didn't go far enough, or we're just all a bunch of leadfoots. It's worth noting that CAFE numbers are calculated off the EPA test numbers, not the published numbers.
I still think it's all driving style in given conditions. After all, C/D managed to get 16 mpg out of a Prius.
I still think it's all driving style in given conditions. After all, C/D managed to get 16 mpg out of a Prius.