Amatsuhitsugi Takamikura (Imperial Sun Succession to the Imperial Throne)' indicates the position that the emperor assumes, and his faculty is the Imperial Throne itself or the administration that the emperor undertakes assuming the Imperial Throne, and it is not supposed to be the rule of succession.
「天日嗣高御座」は天皇が居る場所を指し、その業は皇位そのものか、皇位について行う統治のことで、継承方法のことではないと考えられる。