I don't want to contribute to the debate over whether shoes with advanced technology should be banned or limited in some way so as not to give an unfair advantage. I just want to report a small study that I did on the Vaporfly 4% that, unlike almost all studies, actually used a control to guard against such things as placebo effects. The difficulty until now has been that individual runners are so different in so many respects that, even if two runners with similar Vo2Max, race times, etc. are tested under the same conditions, with the only different being that one wears the Nike shoes and the other a similarly constructed shoe from another manufacturer or another model of the same manufacturer, we can't be sure that the difference in their performance in a race can explained as due to a difference between the shoes. Hence, the design of my experiment:
I wore the Nike Vaporfly 4% Flyknit on my right foot and the Nike Odyssey React Flyknit on my left foot for the whole of a 10k race. I had identical socks on each foot. I began the race with both feet at the starting line. I can report that my right foot finished the 10k just before my left foot. So, my conclusion (albeit this is a study of n=1) is that the Vaporfly does afford a slight advantage to runners, at least in the 10k. I hope to enlarge this study to test longer distances in the future.