Most modern engines with more than 4 cylinders and some with 4 will start "dropping" cylinders at cruise speeds, shutting off the spark and fuel to individual cylinders so the vehicle is only running on maybe 3 or 4 of the eight.
The PCM can change the cylinders around so this is transparent to the driver.
It isn't the same as the old GM 4/6/8 but it traces its roots there.
That aside, as mentioned, many cars have economy buttons which not only change the shift strategies but also the spark and fuel mappings.
I really hate to suggest an additional layer in government, but it seems like an independent FOIA clearing house with the power to indict officials who stall or over redact, is about the only way we will ever get these agencies to let go of our information.