I'm not sure I understand your point. We both agree that the airplane's kinetic engergy relative to the surface of the earth is greater at a greater groundspeed. I never said anything different, in fact I stipulated it in an earlier post. But it does not have any effect on the airplane's vertical speed, in feet per minute, for example. Two gliders would take the same amount of time to reach the earth from the same starting geopotential whether the wind was calm or blowing at an arbitrary speed. The gradients relative to the earth would be different, but not the rates. And turns performed exactly the same way would have identical radii relative to the airmass whether the airmass was moving relative to the earth or not, assuming steady wind of course. It's those differing gradients and groundspeeds that give rc pilots trouble sometimes, not any direct effect on the airplane's performance.