Botvinnik's example and teaching established the modern approach to preparing for competitive chess: regular but moderate physical exercise; analysing very thoroughly a relatively narrow repertoire of openings; annotating one's own games, those of past great players and those of competitors; publishing one's annotations so that others can point out any errors; studying strong opponents to discover their strengths and weaknesses; ruthless objectivity about one's own strengths and weaknesses. Botvinnik also played many short training matches against strong grandmasters including Salo Flohr, Yuri Averbakh, Viacheslav Ragozin, and Semion Furman – in noisy or smoky rooms if he thought he would have to face such conditions in actual competition. Vladimir Kramnik said, "Botvinnik's chess career was the way of a genius, although he was not a genius", meaning that Botvinnik was brilliant at making the best use of his talents.