Shen Mou Hai was one of Casey's main teachers. I actually met Shen on my trip to Taiwan in 1976. Saw him perform in three demonstrations while there. Casey learned from Shen some Tai Chi (Yang Grand Form), Pakua, Hsing-i, chin na and Black Shantung Tiger. Casey said that outside of his original art of Black Shantung Tiger that he felt his best skill was in Hsing-i Chuan. Shen's chin na was brutal so that may have had some influence on Casey/. Casey also learned most of Crown Eagle from Shen and had a partner in Shen's school.