Yes, this is true MOSTLY. Except that a few of the pieces actually require that you visualize, and its traditionally instructed that way, with the visualization incorporated into the posture.
For instance, Sitting Brocade #8 tells you to visualize your entire body is on fire.
The postures are traditionally taught verbally from teacher student. And HOPEFULLY, the teacher has studied the original ancient "secret words", which are the poems used to remember and pass on the postures for the last .
#8
Entire sky slow transportation (Zhou Tian Man Yun)
“Wait until saliva arrives again. Again rinse and swallow the saliva. Do this three times, swallowing saliva nine times. Swallow noisily. In hundreds of vessels, Qi adjusts uniformly and automatically. Entire body transportation (small circulation) completed, visualize that fire is burning your entire body."
The secret words tell you what to focus on during each posture. trust them, or a teacher who refers to them as a guide.
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