kickdown is a way of achieving quick acceleration when needed by sharply pressing the accelerator pedal right down causing a quick change down to the next lower gear. To return to the higher gear, ease the pressure off the accelerator pedal.
This statement was in the slim section dedicated to automatic transmissions. In a manual transmission, of course, you select the lower gear yourself to achieve a quick acceleration. Although this is mainly used when you want to pass someone quickly, it is counter to the emphasis throughout the Guide for ecosafe driving. Kickdown burns through fuel quickly and is not good for the environment.[I needed to add a bit of fun to enliven this otherwise rather dry K-post….]