There have been some great comments over the last couple of weeks. I have limited time at the moment and so want to take the opportunity first to respond to some questions that Psalchemist had posted a while back.
Psalchemist, you asked the following:
<<Firstly, allow me to express my overall ignorance on the meaning of the word 'cross-substantiality' as used in Taijiquan. I am not versed as to the differences between cross-substiantiality, threading and silk reeling. Are these different phraseologies for the same ideologies? Definitions on these terms would be very helpful to my understanding of these subjects.>>
As far as I know, “cross-substantiality” is a term that was spontaneously coined on this thread. It is not a term of art I am familiar with in Taijiquan. However, the concept of the limbs having reverse polarities of full and empty on the same side of the body is one that has been expressed by diverse authorities and seems to be accepted by many within the Yang Style tradition. I cannot confirm, though, that this concept, however termed, is discussed in the classics or in any of the Yang Family writings. I would appreciate it if anyone could point me to any such occurrences.
I can see how “cross-substantiality” might be descriptive of some of things that go on in the body if you do form according to how the Yangs instruct, but at the moment I do not believe it is a concept one should focus on while doing the Yang Family form. As far as full and empty are concerned during form practice, I think one should basically (1) focus on where and when weight shifts occur, (2) stepping without using momentum (however slight), and (3) shifting weight first to the heel, then to the ball of the foot, and then gripping with the toes. In doing push hands, one can then focus on more subtle aspects of Distinguishing Full and Empty that are difficult to train by doing form alone.
“Threading” basically refers to the fact that the Qi should flow freely through each of the joints. The classics refer to threading the Qi through all parts of the body as if it were going through “nine bends of pearl” (jiu qu zhu). I have heard or read this explained in two ways: first, as referring to a pearl with nine bends or holes in it and the difficulty of successfully threading something through the pearl, and second, as referring to nine pearls threaded on a string. The nine bends or nine pearls refer to nine major groups of joints. (I think I have heard nominations from the following ten groups: ankles, knees, hips/kua, “waist,” spine, neck, shoulders, elbows, wrists, fingers/fist.) The string that threads them together is the Qi that leads the Jin. Any blockage in a “pearl bend” (i.e., a joint) will prevent the energy of the string (the Qi leading the Jin through the body) from acting as a unit and achieving its purpose.
For me, threading refers to a particular way in which you use and relate to your joint movement. It is not merely about imagining connections through the joints. For me, it is different in character, rather than in intensity, from ordinary movement and from the movement style I believe is used in Karate and similar martial arts. I can make an analogy to the way the different folds of an accordion relate to each other. It is not really that the different folds are “coordinated” in their movement, but rather that the same impulse simultaneously determines and unifies their movement. The way gears operate would be a similar example. One rusty joint can mess up the entire system.
“Silk reeling” refers to spiral, or rather helical, motion. I believe it is a reference to how silk fibers are spun together to make silk thread or perhaps to how the silk fiber unwinds from a cocoon during the same process. If you look closely at any natural fiber cordage, you will see a helical/spiral pattern in its makeup.
Silk Reeling is said to unify the circular with the straight and Yin with Yang. It is the characteristic and most prominent use of energy of Chen Style Taijiquan. Some Yang Stylists also talk about silk reeling and practice various types of silk reeling exercises. Some do not practice particular exercises, but still assert that the Jin moves through the air or through the body in invisible helical patterns.
As far as I can tell, Silk Reeling does not play a significant part in the Yang Family’s instruction. Here and there, they explicitly exclude some types of “spiraling” from what they consider proper movement for traditional Yang Style. For example, they do not spiral the hips or the shoulders, but keep them level at all times during the form. They also talk about sinking the Qi to the Dantian, but I do not think they want you to try to spiral the Dantain. Various rotations of the limbs do indeed play a major role within the Yang Family system; but as far as I am aware, conscious rotation always has a specific purpose that never includes simply moving through the air or generating or absorbing power.
Please note that there is a concept called “Drawing Silk” that is not the same as Silk Reeling. Ages ago on this forum, I was set straight about this issue. I believe “Drawing Silk” has to do with moving Jin in a way that is delicate, firm, and continuous. The term refers to the right touch that must be used in pulling on yarn as it is formed from silk fibers during the spinning process. An uneven pull will break the yarn, by focusing force on the individual fibers, rather than on their unified force.
Psalchemist, you also mentioned Peng and relaxation in your post. According to my understanding, the Yangs teach that if you “relax” properly, Peng, in the general sense, is automatically present. I have put “relax” in quotes because different people seem to mean different things by this word. In my opinion, focusing on minimizing muscular exertion is not at all what the Yangs mean by “relax.” In my opinion, your progress in their system will be greatly hobbled if you think about “relaxing” in this way. I have posted my share of rants on this issue in the past, so I will try not to repeat myself further here unless someone finds my comments mystifying.