Izawa's theory is not convincing because of the following: (1) it simply and fully accepts Umezawa's view (2) it fails to examine the onryo of the Asuka period, including those of Prince Arima and Otsu (both of whom are considered to have died because of false accusations), and, therefore, (3) it concludes that the case of Prince Nagaya is epoch-making.
ただし、井沢氏の説は梅原氏の説をほぼ全面的に承認しての論であること、また、有間皇子・大津皇子など（いずれも冤罪で亡くなったと思われる）の飛鳥時代の例がとりあげられていない点など、長屋王を画期とする点でも問題が残る。