After Tadahira, Sekkan (regents and advisers) was established as a central post in the government and also the framework in which only descendents of Tadahira were able to become Sekkan was established.
忠平以降は朝政の中心としての摂関が官職として確立し、忠平の子孫のみが摂関に就任するという摂関政治の枠組みが確定した。