I agree, and if they had laboratory tests proven factual this would be helpful to the skeptics. But at this time all we have is road tests.
My hope is they will take time and money and invest it in lab tests. At that point their percentages would be facts and not opinions.
We all know the benefits of good gas mileage but proving it is much different in controlled laboratory situations, then against road testing. At this point I believe automakers will have to see the actual results of lab testing. Thanks for the note,, Val :-)