The $SPX CAPE ratio just hit 41—second highest reading in history. Only the dot-com peak in '99 was higher.

This doesn't mean crash tomorrow. Valuations can stay stretched for years. But it does mean the market is pricing in flawless execution, perfect growth, no accidents.

When everything must go right for prices to make sense, that's when you should be most careful. Not panicked. Just careful.

Expectations are embedded in every price. Right now, they're sky-high.