Kay-shan remained in Foshan, where he became friends with other Wing Chun notables like Ip Man, Yiu Choi, Yip Chung Hong, Lai Hip Chi, Tong Gai and others. Yuen Kay-shan became close enough with Yip Man that he taught Yip's son, Yip Chun, the first form of the art. In addition to having a high caliber skill in Wing Chun, Yuen Kay-shan had also been an educated man who had worked as a part-time lawyer. By being an educated individual he was also one of the first Wing Chun masters to document the theories, concepts, philosophies and strategies of the system. He is also considered a major contributor to luk dim boon gwun and had at one point was even challenged by a monk from Jianxi Province. Death waivers had been signed and the duel had taken place in the Palace of 1000 years longevity. Both fighters were armed with iron poles. Yuen Kay-shan disarmed the monk and spared his life in the duel not only demonstrating his skills in kung fu but also demonstrating his nobility as a martial artist. Yuen Kay-shan never looked for fights, but when challenges could not be avoided, Yuen Kay-shan took them as learning opportunities. Of the 1000 death duels Yuen Kay-shan fought in he was never defeated. Sum Nung Yuen's disciple at first didn't believe he could learn anything from Yuen because he was already proficient with the Wing Chun he had learnt from Cheung Bo, so as a test Yuen placed a raw egg in each of his 2 pockets and challenged Sum to break an egg while he stood in the middle of a circle on the ground, Sam could not break an egg or even push Yuen out of the circle after this Sum was convinced that he could learn a lot from him and was now his disciple. Ip Man movie controversy Sin Kwok-lam (Ip Man's son's student and producer) apologized and served tea to Yuen Jo Tong for misrepresenting his grandfather Yuen Kay-shan's reputation and status in Wing Chun history. (In the movie, Yuen was portrayed as Ip Man's younger kung fu brother, not as skillful as Ip Man). This had the Yuen and Yiu families criticize the movie in interviews. After the Yuen and Yiu families voiced their displeasure about Yuen's portrayal in the movie on Ip Man, movie producer Kwok Si-lam and co-producer Ip Chun apologized