Li Yaxuan was one of Yang Chengfu's top students. He lived in Sichuan after the Second World War and died in 1976. One of his students Zhang Yijin has written Authentic Principles of Taijiquan (Taiji Quan Li Cuan Zhen) to celebrate his art. The book's third edition was published in 2003. The book includes many essays on Taijiquan. The following vignette is from his essay, On the Practice and Cultivation of Taijiquan.
One early morning when we were chatting on the steps under the eaves I felt some discomfort in the yao and automatically rotated my yao and kua several times. he glared at me briefly, and I knew trouble was brewing. After a while he said coldly, "There is no such movement in Taijiquan!" Taijiquan dominated his life; he used Taijiquan principles to guide his daily activities, and he severely demanded that his students adhere to Taijiquan principles.
I have a stiff neck. As one of my warmup exercises I rotate my neck. I try to be mindful of Taijiquan principles: to let yi guide my rotation and with slightly bended knees to sink qi to my dantian. What else should I do to avoid Master Li's cold stare?