How much of that 19 minute gap do you think is just aero drag vs the mental side of it? Because I've done the same kind of test and the wind one hurts twice, once when it's actually pushing you back and again when your brain gives up a little because you feel slow. When there's no wind you just lock into a pace and hold it, but into a headwind you keep checking your speed and getting annoyed, and that alone costs you. The aero part is real, I'm not saying it's fake, but I bet if you did it with the same power the whole way the gap would be smaller than 19 minutes. The crouch position makes a huge difference too, like getting low on the bars can save you more than you'd guess when you're fighting wind. So the physical cost is maybe 12 or 13 of those minutes and the rest is your head messing with you.