Aloha,
This question comes up a lot on the phone (and I'm sure to Chunyi in class).
You'll notice that on the audio cassette/CD #5, Chunyi mentions to do this exercise with you eyes open. However, Chunyi doesn't mention this on the VHS Tape/DVD section of the course -and that is what people tend to go to before stepping into tape/CD 5.
You may find that some days you do well and others you wonder when you stepped onto a tight rope.
Feeling and working with the exercise, and finally stepping into the emptiness is more important that how perfectly one bends their knee, etc. A lot of people tend to worry about tipping over, or are a little intimidated when doing this exercise around other people. Being in their heads rather than the emptiness, had something to do with Chunyi now teaching it in his level I classes with the feet flat on the floor throughout the whole exercise.
This isn't the only change to the Seven Steps of New life exercise. There was more to it even before the version you have learned in the home study course. Master Lin keep looking for ways to simplfy the work so all can get the benefits.
There is focus, energetic, and healing benefit in physically doing the leg work as in the course.
One's physical balance is an indicator of more than just functional proprioceptors and inner ear functioning...it can mirror ourselves physically, mentally, emotionally and spiritually.
One can start with the feet flat on the floor while getting initially experiencing this powerful exercise. After this initial period, consider incorporating the legs and developing your balance (and more), in this exercise from what Gallen and others have contributed above. There are a few times when I'll do this exercise with my feet planted (long flights are a great time for this and the Small Universe), but 95% of the time I incorporate the leg work –maybe it’s that martial artist background, or the kinestetic-lover in me, who knows.
We have Chunyi addressing this exercise and many other things at the 6 Day Healing Retreat in a couple of weeks. Perhaps Gallen, myself, or another Forum participant attending will address this post afterwards.
Much Love, Shawn