[inputcoffee]

The author’s claim only applies to weak form of market efficiency.

The original Fama paper distinguishes between three forms of the EMH: weak, semi strong and strong.

The weak form only alleges that historical price info is fully incorporated in the current price. You can still make money by working hard and figuring things out from outside the price history.

The weak form applies to purely technical trading that extracts value from price history like momentum and the simple moving averages cross over studies you see.