He wasn’t exactly flat out on all the climb though was he, he was talking to Ryan Mullen and the camera, and talking pretty well at that… Not sure you would be able to do that in a 20 minute all out effort, I certainly cant. His power was also up and down as he tried to hang on and race, rather than a steadier effort that would have probably given him a better time. Even so 4.2 W/kg as a starting point is still massive