That is, in hovercraft. You probably would never notice it unless you had a hovercraft that could fly in the air about 100 meters or more. Whenever I am not "hovering" over the ground, reverse is pretty much the only direction I can move in. My forward and strafing velocity are extremely limited (probably 1/10 the speed they're sposed to have).
That is what was done to stop hovering, was in 1.2 but not to such a high effect, so infinite flight could be attained.