These theories have existed for some time, but since the claims that Shingen and his wife were on bad terms with each other, that Yoshinobu was disciplined for his mistake in the Battle of Kawanakajima and refrained from battle, or that Shingen wanted Katsuyori as the rightful heir after Yoshinobu's death cannot be confirmed, they are unconvincing.
これらの説は以前から取りざたされてはいるが、信玄と三条夫人の仲が悪かったという事実は確認できない、川中島の合戦の失策で義信が謹慎したり出陣を控えている事実も確認できない、義信の死後に勝頼を正嫡にする事をためらっている事など、いずれも説得力に欠けるとの指摘がある。