What’s that based on?
If you go back 40 years, no one would thought swimmers, runners, and just about everyone would be as strong and as fast as they are.
I’m sorry, but I’m not buying Coggan is the absolute authority on this. Rules of thumbs are just that, rules of thumbs.
< has done plenty of scientific and engineering modeling in other disciplines. I know full well the shortcomings of models and data collection. Consider how different power meters can vary 5% from one brand to another, and that alone can swing numbers greatly.
5% +/- at a real 350 watts could show up as 332w or 367w. That’s a big swing and hugely effects those w/kg charts. This is also why I take anyone’s self reported FTP or w/kg with a grain of salt.