You will lose mileage but it WON'T be "just as bad" as the loss seen in gasoline engines. Diesel engines don't have as wide a swing in numbers as the gas engines do
True, but real world numbers on diesel engines are much closer to the ratings because they don't have such wide swings at gas engines do.
We all know when looking at EPA MPG numbers that "Your mileage may vary". And in the real world, you will not be able to bank on getting 28MPG all the time with the ecoDiesel. But you can bank on getting consistently BETTER MPG than you would be getting with a gas engine. And most likely, the real world numbers will be more impressive because even though the Ford ecoBoost supposedly gets 22MPG, nobody I know gets close to it. They all seem to run around 13-18. On the other hand I truly believe that many ecoDIESEL owners will run within the 20-25 MPG range.