That is definitely right. My master always instructed me by movements rather than by explaining them. He would explain the principle in a few words after I had experienced the results of the practice method. Gradually I understood the principle. It is none other than entering by doing. It became evident when I practiced the Gun-gon danbup because the mysterious phenomenon that master explained actually happened to my body.
There are 10 stem danbups in the Gun root danbup and 12 stem danbups in the Gon root danbup. Finally there is the Juasa-bup (sitting posture). So the Gun-gon danbup is formed of 23 haeng-gongs (motion (posture)-breathing).
Phenomena beyond the boundaries of common sense become activated in the Gun-gon danbup haeng-gong. One is the skin pore breathing through the whole body and another is the circulation of energy through the function vessel and the control vessel.

In my situation, since I practiced with the one thought by focusing all my strength and maybe because I practiced inside the mountains, I began to feel the phenomenon of won-gi (vigor) accumulating halfway through the won-gi danbup. The energy accumulated in the lower danjun. And then a lump of flaming red heat rushed up. This is called Do-tae (pregnancy of Dao). This phenomenon can be seen as the entry into Sundo practice.
If the practitioner cannot treat the accumulation of won-gi (vigor) correctly then he could face a troubled situation. Practitioners can be seriously damaged if they don't get instructions from their teacher about how to cope with it.
One should practice the way of circulating this self accumulating, large amount of energy by first raising it through the control path on the back of the spine, spinning it around the head and back to the distance of the ears, and then down the front side of the chest’s function-control vessel, and finally back to the lower belly. This energy circulation is completely accomplished when you practice the Shin-bup of Gun-gon danbup.
The very difficult skin pore breathing method can be acquired by the body through the Jin-gi (true energy) danbup which is practiced after Won-gi danbup. And more pore breathing is acquired by the body during Sam-hap danbup.
The essential practice of Gun-gon danbup is circulating the function and control path. I was ordered to circulate it once a day and I did what I was told. One must pay attention to danjun breathing when doing it. Inhale energy and keep it in the lower danjun for a while. Lower this energy with the hot energy gathered from the danjun to the anus, roll it through the spine and raise it to the level of the back of the ears as I mentioned before. Then spin it back as far as the ears again and lower it to the neck, chest, and to the belly, and finally when the energy arrives at the lower danjun, exhale the energy that was inhaled. This is practiced by respiration, but the circulation of the function and control vessels is done by thought. And that thought comes from bearing the heart. When this becomes skilled, the strength of hot energy actually circulates physically. This is what one senses and realizes in the Jin-gi danbup.
Follow the rules of the 23 motions (postures) and control the breathing when doing Gun-gon danbup. This is called 調息breath control. Inhale and hold the energy in the danjun and then exhale and hold again. Regularly control the time of inhalation, exhalation and holding to be the same and practice each of the 23 motions (postures).
The most efficient time to practice is between 丑Chook hour(1~3 am) and 午Oh hour(11am~1 pm).