He was apparently not very proficient at Japanese and Chinese classics, evidenced by a comment made by Chikanaga KANROJI in his diary that, 'Suketsuna is not good at Japanese and Chinese classics' ("Chikanaga kyo ki" [Diary of Chikanaga KANROJI]).
ただ、和漢はあまり上手ではなかったようで甘露寺親長からは「和漢ども堪能にあらざるか」と評されている。（『親長卿記』）