When it comes to calculation, the biggest difference between a Grandmaster and a Pooch is not depth of calculation or accuracy of calculation... it's the intuitive choice of WHEN to calculate and WHICH moves to analyze. Only experience teaches that.

Couldn't agree more. Knowing when and what to calculate is incredibly important. Also, being good at visualising the board and seeing several moves deep is worthless if you are bad at tactics. It is pointless to calculate 5 moves ahead if you will be missing all the tactics that will occur just 2 moves deep.

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