To prevent his clan's military secrets being leaked by Kazumasa to Hideyoshi, Ieyasu hurried to change his military system adopted since the time of Mikawa to the military system of Shingen TAKEDA.
数正によって秀吉に自家の軍事機密が流出するのを防ぐため、家康は急遽三河以来の軍制を武田信玄の軍制に改めた。