This theory argues that the reason why the due description does not appear in the Emperor Monmu's imperial edict upon enthronement is because Fukai-no-Joten/ Fukaijoten did not exist at that time, and when the enthronement of Empress Genmei was to be celebrated or just before it, the code was created in order to justify the direct line (or the legitimate child) succession.
文武天皇の即位詔で現れないのは当時不改常典がなかったからで、元明天皇即位の時かその直前に、直系（または嫡系）の継承を正当化するために創作されたのだとする。