Personally, I think: Teacher Zhu Datong is great. He is the first person who can spread his internal skills so easily. Zhu Datong studied under Yang Yuting, Wang Yongquan, Wu Tunan and other masters in his early years. These three masters are all masters with profound internal skills. Especially in his later years, Yang Yuting went to his home to study boxing for nine years until his death. Zhu Datong did get the true biography and essence of Taiji's internal skill, which is also obvious and beyond doubt (as for the depth of internal skill, everyone will judge for themselves). His "Revealing the Secret of Taiji Internal Strength" and "Chapter 13 of Taiji Internal Strength" are all good explanations, and there are also Taiji Eight Diagrams, Yin and Yang, Taiji Feet and so on. I have read both books and discs, and I agree with them very much. (But it needs to be clarified that there is more than one way to practice Tai Chi, so his exposition may not be comprehensive, but it is more correct. ) Zhu Datong doesn't talk about routines, only makes sense, which is very rare. Especially now, teachers are everywhere, and students are hard to find. Whenever a student asks: What genre of boxing is good? All the teachers say it's good to practice this, but the students are in a fog and don't know what to do. In fact, genre routines are just a carrier, and each routine can practice internal skills. Everyone should choose a routine that suits them or is easier to control, and have a clear goal, use the right method and make unremitting efforts (all three are indispensable) to practice internal skills well. From this point of view, I think Zhu Datong still has real talent, and he is by no means a liar. As for whether practitioners can understand it or not, it's just that their personal level is different.