They compare it to Oscar Pistorius' legs or the Speed swimsuits.
Science of Sport wrote:
Basically, I think there are two historical cases in play: The Pistorius advantage, which draws a direct line to this, and the Speedo LZR Racer swimsuit and subsequent suits, which illustrate a couple of conceptual issues....
To sum my position up, I think the addition of any device that purports to act as a spring (and the Vaporfly Elite clearly has this) should be banned for the credibility of performances both now and into the future...
My position would be that any device inserted into the shoe, and which purports to add to energy return or elastic recoil or stiffness should be banned. That means the carbon fiber plate, or plastic etc but not necessarily the gels/air patches that offer cushioning, and not the foam, either. Since Kram raised it on Twitter, I also don’t think that orthotics meet that standard to be banned. I’m talking specifically about a device that is there to ‘spring’ by offering elastic recoil, and that’s what a carbon fiber plate is doing when it’s curved in the way that this particular one is.