Hypothesis is the key word. It's not a law, or a tested theory. Also, it's predicated on all participants having perfect info, which doesn't happen in the rea

Hypothesis is the key word. It's not a law, or a tested theory. Also, it's predicated on all participants having perfect info, which doesn't happen in the real world. Is it useful? Mostly no, in my opinion, other than realizing that when my own idea of valuation differs from the market's, it's usually because I'm missing something.