Unwanted pedal movement wastes fuel.
Even the best drivers change requested power several times a second.
As a vehicle travels forward, it also moves slightly up and down due to variations in the roadway surface. This motion in turn causes the driver’s foot to change pressure on the accelerator pedal, leading to slight changes in power.
For example, a driver targeting 35 MPH may unintentionally change requested speed between 34, 31, 37 and 32 MPH in less than a second.
Individually, these deviations occur so quickly that they usually pass unnoticed by the driver. Yet together they significantly reduce a vehicle's real-world mileage from its theoretical peak.