No, you're not grabbing at straws. They're closely related. Takeuchi-ryu is actually on of the main schools responsible for the formation of quite a number of koryu bujutsu schools in the Kansai and Kyushu areas of Japan just as Tenshin Shoden Katori Shinto-ryu is for Kanto. The founder of Takeuchi-ryu, Takeuchi Nakazudayuu Hisamori taught a number of individuals who went on to form shiryu (branch or offshoot schools). According to Takeuchi-ryu historical records, students of Hisamori include, Futagami Hannosuke Masaaki and Toda Gorobei who later formed their own schools (Futagami founded Sosuishi-ryu and Toda Gorobei founded Toda-ryu Kogusoku). Hisamori's grandson, Takeuchi Kaganosuke Hisayoshi had an even deeper influence since he travelled around the country on musha shugyo and engaged in many taryu-jiai. His encounters influenced the development of such schools as Hontai Takagi Yoshin-ryu, Rikishin-ryu, Araki-ryu, Araki Shin-ryu, Nanba Itto-ryu, Fusen-ryu and Kyushin-ryu. His experiences also influenced the evolution of certain kata in Takeuchi-ryu's system. Swings and roundabouts.