What is the history of this form? The version I learned in Goju-ryu was extraordinarily simple--just a run-through of the basic blocks and punches that was all but stationary--but I know it is a bit more involved in some systems, e.g. Washin-ryu, in which it includes for example an unusal technique of drawing back into a cat stance, bending at the waist, then moving forward in this bent-over psoition while doing a double backfist strike (like the Tai Chi boxing ears move but bent forward).