It involves the Root Chakra, which is located directly at the base of the spine, also known as the coccyx. The chakras have their own mystic qualities, I guess. I don't know for sure, but they do seem to be located in parts of the body where bunches of nerves meet. (The Vulgano version is situated half way between the places we do our number one and number two in the restroom.)
In practice and in theory, imagine (and feel) a ray of some sort (red is the most common mystic color associated with the root chakra) shooting down into the ground while playing. For high notes, imagine (and feel) a more intense ray. If we practice this sitting in a chair, we can notice all kinds of muscles come into play, which happen to be the same muscles used to "support" the air stream. By taking attention off of the mechanics and experiencing the mysterious, magical and not yet patented RAY OF POWER we can avoid some of the tension involved in "trying hard."
Nothing mysterious and magical here really, but the RAY OF POWER does permit me to play with a relaxed but working body.