Rephrase:
1) Play the cards.
2) Play the players.

In both cases, you are removing a degree, x, of imperfect information and making it perfect. In any discussion of poker hands, the "it depends" comes from not knowing what your opponents are holding, not from not knowing what the next card will be. There's more uncertainty coming from the other players' hands than from the next card. By removing the biggest x possible, you will be increasing your profits by the greatest amount.

Poker is a game of people played with cards. Knowing your opponents is more important than knowing the next card.