Isn’t that the null hypothesis?
I have these data points:
1) The pool is shallower than normal in this Olympic
2) The pool seems to be slower this Olympic
3) swimmers seem to think it’s because the shallower depth
4) people responsible for building the pool say the effect of depth is negligible
5) there are other things that can be different about the pool except depth because the pools aren’t strictly standardized in their properties
My only claim was that point 3 doesn’t tell me a lot because I find it very plausible that you can’t really detect the reason for the slowness just from swimming. I don’t have positive proof of that though.