Maybe, but it's close. Obviously at higher speeds frictional resistance is a much larger percentage of the total. I've been steady at LT at 10 mph, full tuck on the aero bars, pulling my hill leader on the flat. Didn't have a wind-speed meter, but from sailing I guessed it as about 30 and an apparent of 40. Even a small difference in estimated wind speed makes a major difference, from the law of squares, so I could have been wrong about the wind speed by say 5 mph.

But what I want to know is what does your PM say when you're doing that? Do you get 300w-400w at 10 mph? Because physics says you shouldn't. Reductio, if you were in a wind where you could hardly turn the cranks, the PM should say near zero, regardless of RPE.