Even at highest levels players make significantly but human mistakes. On the other hand there exist a great opening theory with lines studied in deepth, especially the mainlines. Isn't the precision of theory evaluation and human imprecision contradicting? Is it generally difficult to punish small opening sins even at the highest (human) level (Evans-Gambit, Cozio defense, 1. ... a6)? If so is the fact that most advanced players learn and play some kind of mainlines just some kind of gentlemen's agreement? Or do they score significantly better?

Even at highest levels players make significant, but human, mistakes. On the other hand there exists a great amount of opening theory, with lines studied in depth, especially the mainlines. Isn't the precision of theory evaluation and human imprecision in contradiction? Is it generally difficult to punish small opening sins even at the highest (human) level (Evans-Gambit, Cozio defense, 1. ... a6)? If so, is the fact that most advanced players learn and play some kind of mainlines just some kind of gentlemen's agreement? Or do they score significantly better?

In 1980 Miles played 1. ... a6 against Karpov, who couldn't take any advantage of it (and even lost). Is it generally difficult to punish such small opening sins even at the highest (human) level? If so is the fact that most advanced players learn and play some kind of mainlines just some kind of gentlemen's agreement? Or do they score significantly better?

Even at highest levels players make significantly but human mistakes. On the other hand there exist a great opening theory with lines studied in deepth, especially the mainlines. Isn't the precision of theory evaluation and human imprecision contradicting? Is it generally difficult to punish small opening sins even at the highest (human) level (Evans-Gambit, Cozio defense, 1. ... a6)? If so is the fact that most advanced players learn and play some kind of mainlines just some kind of gentlemen's agreement? Or do they score significantly better?

In 1980 Miles played 1. ... a6 against Karpov, who couldn't take any advantage of it (and even lost). Is it generally difficult to punish such small opening sins even at the highest (human) level? If so is the fact that most advanced players learn and play well-known (but good) opening theory mainly just some kind of gentlemen's agreement?

In 1980 Miles played 1. ... a6 against Karpov, who couldn't take any advantage of it (and even lost). Is it generally difficult to punish such small opening sins even at the highest (human) level? If so is the fact that most advanced players learn and play some kind of mainlines just some kind of gentlemen's agreement? Or do they score significantly better?