Hi Dan and Fumin,
You both are describing some interesting images. Metaphors like these can be helpful to some people in refining their practice. As you may recall, Louis led a thread on metaphors a couple of years back that was also quite interesting.
As I think about water metaphors that might describe the 8 Jins in the manner I described them earlier, I keep bumping into the fact that the intent or feeling of the opponent seems to be a critical component. In other words, any physical metaphor leaves an important piece missing; nevertheless, let me share a few that might describe at least a part of my views.
Water is an interesting metaphor, not only because of the specific connotations it has in traditional Chinese culture, but also because it is a medium that can make visible various types of energy in the Newtonian sense. The energy itself has no form, but it can nevertheless give shape to water it encounters.
First, as I understand the Association teachings, Pengjin, in the general sense, is something that arises simply by consciously loosening and extending the joints. Nothing more is really required; however, to make it useful, you need to “shape” the Pengjin with your intent. In this sense, I can liken the feel of the joints to ice, water vapor, and liquid water.
When the joints are stiff, they make the body into a block of ice. Even though the body is unified in a sense, it has little ability to change, little ability to show Yin-Yang alternation.
When the joints are completely limp and without energy, they make the body amorphous and weak, like a cloud of water droplets. Change is quick and easy, but there is no stability. Again, there is little ability to show Yin-Yang alternation.
When the joints alternate between stiff and limp, they make the body like snow. Parts can be soft and cottony; parts can be sharp and lumpy. Although there is Yin and Yang, there is really no feel of alternation. The body is a mix of Yin and Yang, but does not show the dynamic interplay of Taiji.
When the joints are loose and extended, they make the body like water. All the parts are joined, but in a fluid, rather than a rigid way. Individually the parts are weak, but together they have the power of a strong wave. The effect can be soft and gentle, like floating down a stream, or hard and powerful, like the feel of water gushing out of a fire hose.
As for Wardoff energy specifically, I would make an analogy to walking waist deep into a rip current or a flooding stream. The opponent “steps” in; and although he feels he can touch bottom, he cannot resist the relentless flow and is swept away.
In the basic Wardoff application I described in a previous post on this thread, your forearm is placed behind the opponent’s arm and directs energy behind the opponent’s shoulder to sweep his body away; however, even in the basic one-hand horizontal push hands circle, the energy is similar. Using sticking (Zhan), you tend to sweep the opponent out of his root, even though you are pulling only the opponent’s energy, and not his actual arm. In this case, I prefer this imagery of sweeping to imagery that implies that you are repelling the opponent’s energy from your center. Any idea of “repelling” tends to lead to the fault of resisting and gives the opponent a sense of a “hollow” or “projection” at the point of rotation that he or she can push against, even if you keep your arm perfectly round.