1/4 inch high closed cell foam draft insulation tape.

Don't care if drag is increased - we're trying to increase MILEAGE.

Shark skin is "dimpled" or otherwise non-smooth. In rowing, the new carbon fiber shells have shark skin type coverings instead of smooth over fiberglass or wood. Why? They decrease drag through the water. Whether it's NET drag or immediate drag, I honestly don't know why we'd care.

Same principle applies here. By the way oranges are also aerodynamic with their "orange peel" skin. They don't normally move but if you've ever seen a cruddy paint job with "orange peel" (water in the paint usually), this type of paint job helps aerodynamics. Decrease cD for those who care.

So if dimpling, shark skin or orange peel effects help aerodynamics, you'll be helped with this type of covering. Anything that has a NET effect of getting the car through the air with less effort, even if it increases drag directly ON the skin but the surrounding air becomes net slipperier, then I say use it.

The Corbin Sparrow uses dimples at the trailing edges. Look at the body above the rear wheel, and the back of the front fender. Here's a pic:

https://myersmotors.com/im1/home_full/full_2.jpg

Never noticed that before. Seems to suggest that they may need to work under more dynamic orientation to the direction of travel. I have read of owners finding themselves pointing the wrong way after braking and turning too quickly!