What is GTO?

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1. 0:00Pocket aces on the river. The solver moves all-in half the time, and checks the other half. That's not a glitch. That's GTO.
2. 0:08Game theory optimal. A strategy that holds up even when your opponent knows exactly what it is.
3. 0:14If aces always bet, every check would be weak, and easy to attack. Mixing protects both lines.
4. 0:20Solvers find this by playing the strategy against itself, over and over, keeping whatever wins more.
5. 0:26Until neither side can gain by changing. That's a Nash equilibrium.