From No Limit Hold 'em: Theory and Practice p124
In deep stack no limit, preflop hands derive most of their value from how well they extract money after the flop from your opponents. Comparing hands based on how often they win a showdown or on their poker "hand rank" is worse than worthless.
I would think comparing hands based on how often they win a showdown or on their poker "hand rank" has some value? What am I missing?