I don’t think the central channel I’m working with lately and trying to describe is the zhong ding that Bob Tangora describes. Bagua goes further.
I posted back in April of 2012 how Bruce had showed me what I called the “dispersion mode” of the Heaven palm. This eventually led me to make a distinction between the center line concept of the central channel (what I think Bob describes and calls the zhong ding) and the core channel which is at every point throughout your entire field inside and outside the physical body.
This summer at the Water palm change, Bruce helped me understand how to more fully open the psychic channels. which culminated in a peak experience about a month later on top of a 9,000 foot mountain near our Wyoming home.
I only mention this because it is one of the important distinctions between what I think Bruce is teaching in Bagua and what Bob calls the zhong ding. It is why Bruce has said that you first open the lower tan tien, then the upper, and then the lower and upper open the middle tan tien. Without the support of the “psychic” channels (just think of this as a particular collection of channels and don’t get hung up on all of the typical associations with the word psychic), you can’t access the core channel or the central channel that Bruce describes.
In the BMP, you find the zhong ding (center line) then you start opening it up slowly and methodically. Finding and working with the center line deep inside the body is not easy and takes a lot of time and dedication. But that is only the first step. Next, you have to start connecting to it. Everything that Bob describes is part of the process but IMO it is a small subset of what Bagua is trying to achieve.