Originally Posted by
Campag4life
No it isn't for the reason I explained with due respect to FB. The reason is..when the wind is at a rider's back the force of the wind is acting on a smaller drag coef....a convex surface versus a direct headwind where windspeed + bike speed is acting on a concave surface resulting in a higher drag coef. Putting it in more layman's term. The body from behind is less of a sail then a wind into the body. The body natively catches more air when wind is into it.
If the wind at your back is higher than your ground speed, I think you might be onto something. But at +/- of that much wind the differences on drag will be much higher than due to different drag coefficients. Because of the old V squared drag thing.
The wind in front always produces more drag than the same wind reduces in back. Because drag proportional to apparent wind speed squared.