Roman's Lab DVD Vol. 53: Improve Your Ability To Calculate Variations, by GrandMaster Roman Dzindzichashvil, is a part of Roman's Getting the Edge in the Middle Game Series.
In this volume, Roman teaches that there is no exact theory on how to calculate, but gives instructional examples on calculating critical positions and why to avoid wishful thinking.
He also explains the importance of calculating from both sides and that intuition is an essential part of calculating. This will help you narrow your search on what variations to play. After all, Roman says, without intuition there is no calculating.
Grandmaster Roman Dzindzichashvili:
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