Well... its not taijiquan but there is a set that might be able to shed some light on it... in Korean it is called Keum Gan Kwan... diamond fist...Jin Gang Quan in Chinese. It was a qigong set taught at Songshan, or so it is said anyhow, to strengthen the older monks. Not Taiji, but close... and reminescent of the Chil Sung in my mind... very close in principle.