Isserson is one of the fathers of the deep battle doctrine and was one of the most brilliant minds of the Soviet Army. (According to Joukov's memoir)
However, Isserson was also described as an awful leader on the field. He lost many exercises during the 30's (Also when Joukov was the CO of an armored division) and he was supposed to have some issue with interpersonal relationships. Is there any report of his experience on the field to prove his unability to lead men ?