Review: 'GTO Poker Simplified', by Dara O'Kearney and Barry Carter

Haley Hintze Author Photo
Haley Hintze
Posted on: December 26, 2022 15:14 PST

Poker strategy books have changed. Gone are the grand, sweeping efforts that took on major parts of how poker should be played in one fell swoop. From Doyle Brunson's Super/System decades ago, there's been a shift over the years from that omnibus approach to writing strat books for niche markets. GTO Poker Simplified: Lessons from the solvers that any player can apply to their game, by UK authors and poker players Dara O'Kearney and Barry Carter, spins the current strategy-book reality by taking one of the newest shifts in strategic poker theory, game-theory optimal (GTO) play, and presenting the theory's approaches and findings in a way that many players can understand and apply.

GTO Poker Simplified is a bridge-building effort, too, in attempting to find common ground between GTO and some of the other prominent approaches and debates in modern poker. From an explanation of how solvers can offer valuable training and strategic optimization benefits without being used as live-assistance tools -- a forbidden practice on most online poker sites -- to integrating GTO theory with the HUD-based (Heads-Up Display) exploitative strategy frequently employed by online pros in recent years, the book stands as solid attempt at widening the awareness of how a GTO approach can benefit one's game.

GTO Poker Simplified isn't the first GTO-themed strategy book. O'Kearney, the strategy guru behind the latest of several O'Kearney/Carter releases, fully credits two other GTO books, Play Optimal Poker by Andrew Brokos and Modern Poker Theory by Michael Acevedo. Instead of parroting those, however, O'Kearney, a strategy tutor and a veteran player, explained that the two earlier books, while outstanding in content, lacked an easy way for no-limit hold'em players new to GTO to grasp the approach.

"These books are so good we initially saw no need to write our own book on GTO, and Dara
just recommended both books to all his students," Carter explains early on. "However, he
noticed that many players came back and said they couldn’t really grasp the books without a basic introduction to GTO with practical poker examples, which was the genesis of this book. Our goal is to present the key lessons from GTO in actionable heuristics for players taking their first steps into
game theory or those who have previously struggled to get their head around it.

Readers interested in learning about GTO theory and applications shouldn't confuse "basic introduction to GTO" with any notion that this is a beginner's poker-strategy book. Carter himself admits to struggling to grasp some of the concepts O'Kearney lays out, and this writer can report much the same. GTO Poker Simplified doesn't achieve its goals in grand sweeps, but rather, it presents its ideas in bits and pieces, opening a door here, a window there. The book circles to and fro as it explains what GTO theory is, how it's designed to benefit its practitioners, and why some confounding betting solutions a solver might recommend are, first impressions aside, the true best choices in certain poker situations.

And it's not easy. Though it might be more accessible than its GTO predecessors, GTO Poker Simplified isn't for poker beginners, and it's probably not truly an intermediate-level book, either. It falls on the spectrum between intermediate and expert/pro, and it's designed for players who already play a lot (and who study their games as well) and wish to take their games in a new direction.

More than just range charts

There are a lot of range charts strewn throughout the pages of GTO Poker Simplified, taken from various solver outputs and used as illustrative support for the strategic options being discussed. Within GTO theory, though, the charts themselves are complex. Considering various bet/raise/check/fold options, along with exploring the reasoning beyond various bet sizings, accounts for a lot of that complexity. GTO theory encompasses the entire strategy tree for any given hand, then prunes that tree to optimize results.

"A GTO approach is a holistic approach to poker that takes into account how all your hands play before deciding what to do with the two cards you are looking at right now," the authors write, over a hundred pages in, though the wave of charts presented here might seem anything but holistic. Yet there's a greater point to be made. Each and every hand example works more as a way of training a player how to to think in GTO terms. That applies to live situations as well as online, too.

Defining and defending GTO play is one of the tasks that O'Kearney, the book's strategy wonk, charges into head-on. The book's very first chapter, "Myths about GTO", finds O'Kearney deconstructing many of the arguments anti-GTO players make against the approach. Such arguments include "GTO is just breakeven poker", "GTO is boring", "GTO is cheating", and others. Whether GTO play is the inevitable wave of the future is one of the few questions O'Kearney doesn't really attack directly, preferring instead to contrast it against exploitative approaches and let readers draw their own conclusions.

After exploring the differences between GTO and exploitative strategies and establishing the environment for GTO play, the authors move on to more specific topics. Those topics are often esoteric, including merge bets, range advantage, blockers (and unblockers), board coverage, and much more. There's a lot to digest, and that's all before getting to the second half of the book.

That Part II of GTO Poker Simplified is largely a street-by-street examination of how GTO strategies should play out. However, O'Kearney opts not to present the concepts and explanations in the timeline based order of a given hand, meaning pre-flop to rather, but does so instead in order of importance. That means concepts of betting on the river come first, followed by post-flop, then turn betting, and finally, pre-flop. It all works and comes together in the end, and since this is a book you'll sample in small segments, time after time, it doesn't really matter.

The book closes with a chapter on other GTO considerations that stretch into metagame territory, well beyond the games themselves. Implementing an error-free (GTO) approach only goes so far if the poker environment itself creates distortions. Some of those areas are within a player's control, such as bankroll management, while others aren't, but understanding how it all impacts play is itself a GTO way of thinking, too.

Finding common ground with exploitative strategies

As mentioned, one of the themes throughout GTO Poker Simplified is that GTO-based play is counter to the exploitative strategies employed by HUD users, who accumulate hand histories on their opponents and search for patterns of too-passive and too-aggressive play. In some ways GTO-optimized play is a natural counter-reaction to HUD proliferation, in that its highest aim is to make oneself unexploitable by other players.

In the process, GTO-optimized play, O'Kearney argues, will produce consistent profits no matter what stakes are being played. It might not win as much as an exploitative strategy in certain games, but it should remain profitable in all games. In any zero-sum strategy game, a player's profit comes from the mistakes other players make, and GTO theory is designed to move players closer to that poker nirvana, error-free play.

And the authors allow that, yes, in real-game situations, it's perfectly fine to veer away from GTO-optimized play to take greater advantage of other players' mistakes and tendencies. After all, it's still poker, and it's still a game of limited information. You'll find and understand your takeaways, too, but at your own pace. Did you ever wonder why A-5 suited might be a more successful jamming hand in a short-stack situation than pocket jacks? It's about the blockers, O'Kearney explains. The A-5 prevents one of the four aces from being in another hand, reducing by 25% all the calling hands that include an ace and might be held by another player. Such subtleties epitomize GTO Poker Simplified and can be found throughout its pages.

Does it all work? Probably yes. GTO Poker Simplified takes difficult, cutting-edge poker concepts and makes them more accessible to the masses. Most chapters include heuristics, short summaries of the chapter's most important points, and reinforce how those concepts can be applied in situations at the table. The book wanders a bit in spots and despite its depth and complexity, could have gone on for twice its length, but it's a winner. It's where modern poker-strategy books are at, mining in the deepest theoretical veins of the game. O'Kearney and Carter have authored several strong strategy books in recent years, and this is a worthy addition to the library.