Decades ago, before people approached poker scientifically, poker players had to learn (and play) by the seat of their pants. They would do what seemed right to them, or what they saw other people doing. There was often a herd mentality about various actions – if “everybody” is doing it, it must be correct, right?
Well, no it wasn’t – in fact, careful study of the game has shown that many dearly held beliefs sat on flimsy (or no) theoretical foundation. The herd had, in fact, wandered far from the path of good poker.
In the earlier years of academic poker study, one practice that came under fire was “checking to the raiser”. That is, if a player put in a raise and was called, on the next street people would routinely check to him. It even became a hackneyed phrase: “Check to the raiser” or “Check to the strength.” The limit hold’em gurus of the 80’s and 90’s said that this was a mistake, ceding too much control to the raiser. No less an authority than David Sklansky wrote, `Resist the urge to ‘check to the raiser’.”
Well, like any academic field, poker’s bad ideas are replaced by good ideas, which are ultimately replaced by better ideas. Many of those better ideas are coming from a field of study called “game theory,” the mathematical study of how to win at various kinds of games. This is in no small part because modern computers and software have made it possible to determine “game theory optimal” (“GTO”) approaches to poker. Even a decade ago, it would have been impossible to compute such strategies, but now they’re available to any poker player with a fairly modern computer. Poker GTO is its own topic, and whole books are being written about it, but you can get a good introduction by reading this beginner’s guide to GTO.
Going back to this concept of checking to the raiser, game theory has, in fact, validated what the herd was inclined to do for decades. While there are few absolutes in poker, it turns out that usually the player who has raised (or bet) is likely to have the better hand. In theoretical terms, that player is generally betting a “polarized” range, which gives him an advantage over the player who has checked and called, from a “compressed” range.
As the check/caller, you should be inclined to abandon that pas de deux only if the board card dramatically shifts power in your direction. For instance, suppose you are in the big blind and call a preflop raise by the under-the-gun (UTG) player. The flop is K-7-4, you check and call a bet. Now the turn is another seven. You are much more likely to have a seven than the preflop raiser, so this may be a good time to bet out (whether you have a seven or not). But absent such changes, you should almost always check again on the turn – even if the turn card was your gin card and gave you the nuts. Then it’s probably best to go for a check-raise rather than bet out.
One important example of this is that you should rarely lead out (“donk bet”) into a preflop raiser after you have called out-of-position before the flop. So in the above case (the UTG player raised and you called in the big blind), checking nearly 100% of the time on the flop is correct, whether you intend to fold, call, or check-raise. I wouldn’t encourage checking in the dark (i.e. before the flop is put out) because that tells your opponent that your decision to check is not based on the board cards. But as a practical matter, this is the best play.
This is a great example of how you can benefit from some understanding of theoretically correct poker, even if you don’t take the time and effort to become an expert.