However, Naohiko YAEGASHI's theory, that seeks evidence by backing Umehara's theory on the demise of the Soga clan's head family (Soga no Emishi and Soga no Iruka), and Kazuomi TADA's view, that points to evidence in the death of Prince Otsu, are logically valid although both refer to writings of later times as proof, including "Fusoryakki" and "Yakushiji-Eng".
蘇我宗家（蘇我蝦夷・蘇我入鹿）の滅亡にその兆候がみとめられるとする八重樫直比古のような理解や、大津皇子にその発端をみる多田一臣らの説は、『扶桑略記』『薬師寺縁起』のように後世にくだる史料に拠らざるを得ない欠点はあるものの、一定の論拠を有している。