I would just like to comment on an interesting idea. When Chatan Yara learned in China, according to Richard Kim in Weaponless Warrior, he learnt Hsing-I and Chi Kong. Upon returning to Okinawa, he blended the concepts of Inner Power and Balance, he had learnt from that study. When one investigates the lineage of Hsing I Chuan, it would appear that Wong Chung Yoh may have been a boxing brother with Ji Leng Feng, from whom Dai Family Xin Xi was derived from. I would suggest that the possibly what Chatan Yara learnt was not Hsing I Chuan, but Xin I Chuan.
Modern Xing Yi Chuan or Hsing-I Chuan was developed by Li Laoneng (1805-1885), so Chatan Yara would not have learnt this form of Hsing I Chuan.
Master Hirokazu Kanazawa had learnt Yang Style Tai Chi Chuan. When I spoke with my Tai Chi and Hsing I instructor, Master Wang Fu Lai in 2001, he stated that he had taught Mr. Kanazawa the Wu Hsing I Chuan during the early 1970's. When one watches Master Kanazawa performing Kata, it is not stiff. He exhibits what Kuo Yenshun would describes as Obvious Cheng. It is not the typical "Kime" that many Karateka presently focus upon. My feeling is that Master Kanazawa has injected elements of Tai Chi Chuan and Hsing-I Chuan into the Karate he now instructs.