Precisely. I studied aerodynamics some in school but never had a reason to really take a hard look at it.
Knowing if everything works half way decent, we should be in the 150-170 MPH range. I know everyone is going that fast or faster. Have you ever tried to stick your hand out the window at say 100MPH. Even at 100mph, the wind resistance is enough to carry extra boost with my old '90 model. Extra boost equates to more power. The slicker I can get the 'Transformer Shop Truck' to cut through the air, the less power I will need to go that fast.
During my research, and watching and reading up on Larry Larson, the more air you can direct up and over the vehicle, the more air you sort of have control over. Also, I didn't see any rules that limits anyone's arrangement of the skin.
An old friend (Joe Hartley) said it years ago, even before we had cell phones, He was late for showing up at the house and I gave him a call. He said I am on my way and "I will have her ears pinned back". lol He used to drive a 78-79 3/4 ton ford around when we were 'Holler Hopp'n' back in the day. He ended up on top of a small car at our local hang out before he started tapering off. lol