The statement only referred to the net motion of the vehicle and the deflected air. The fact that during that process the air here of there had higher or lower

The statement only referred to the net motion of the vehicle and the deflected air. The fact that during that process the air here of there had higher or lower pressure is incidental, and not contradictory to this explanation. The air might have other things changed about it by the process, such as turbulent motion, but again those are incidental and are not contradictory to the general statement.