This is a story that has come down to me about 50th-hand, yet it seems worth telling.
O-Sensei was teaching a class, probably at Hombu Dojo in Tokyo, attended by students whose customary teacher at the time was Koichi Tohei. O-Sensei had introduced a jo kata to them during a previous class that he had said contained 26 moves.
However, on this particular day when he began to run through the kata he told them it had 31 moves. The students became confused, and wondered aloud if it was the same kata, as it seemed to be despite a few differences, that they had learned the day before.
Upon hearing this O-Sensei flew into a rage, shouting at Tohei Sensei, "You idiots! Aikido is not static, it changes everyday. Practice what I'm showing you today!"
Tohei Sensei, thoroughly humbled by the scolding, turned to his students, and whispered, "from now on just ask me."