Farther down the story they say cruise control nets you 7%! Edmunds and Consumer Reports drive like most people drive, so they get bad mileage all around, and report it as such.
What's true for them is true for most, but may not be true for the serious mileage driver.
Yup. My 22 year old engine-idling son finds that cruise control gets him better FE. Presumably because it relieves him of the temptation to stomp on the gas any old time. He has plenty to learn re. FE but isn't toooo interested.
Currently getting +/- 50 mpg in fall weather. EPA is 31/39 so not too shabby. WAI, fuel cutoff switch, full belly pan, smooth wheel covers.