This is partly because he maintained a close relationship with the losing side of the Sekkan-ke, who had been plagued with inheritance battles, which Tameyoshi remained unaware of, even after the the system of cloistered rule had been established and to compete with the Taira clan, who were close to FUJIWARA no Tadamichi, the Sessho (regent), he approached FUJIWARA no Yorinaga, who had been dearly loved by his father, Tadazane, and who looked to have a promising future, helping him become the head of the Fujiwara clan.
それは院政誕生後も相次ぐ家督争いでその風下に立つ事となってしまった摂関家との密接な関係を続けていたのも原因の一つであるが、その事に気づく事無く、ライバルの平氏が摂政藤原忠通と親しかった事に対抗して、父の忠実に溺愛され、有望と見た弟の藤原頼長に接近し、藤氏長者獲得等に貢献した。