So I read through about 2/3rd of the post until OP started throwing out specific numbers. Since my life is based on the principle of fuzzy math, I guess I'm a prime M-taxpayer on paper
But being around cars and modding for so many years, I've learned, like most, that aftermarket CF parts are strictly cosmetic. You are right OP; most aftermarket manufacturer don't have the expertise and/or $$$ to wind tunnel test these aero bits. They just copy visual design cues from the real race cars.