Subject: Re: S&P 500 hits record high
It seems rational and smart to say that you could have "timed the market" and you shouldn't have bought when the trailing P/E of the market was high. Unfortunately, there is no statistically significant correlation between the market's overall P/E ratio and forward returns. This seems counter-intuitive, but it's true.

What about Cyclically Adjusted PE?

Random article:

The Remarkable Accuracy of CAPE as a Predictor of Returns
https://www.advisorperspective...

CAPE:
https://www.multpl.com/shiller...

Currently about the same as in 2001.