This technique incorporates the hanasu idea that sometimes it is more ‘aiki’ to go under the arm than to go around it to get to uke’s back. If you happen to be holding uke’s hand when you make a hanasu #5 or #7 motion then you end up with this technique – the turning wrist twist. It is also possible to get to this position walking around the arm as in hanasu #1 or #3 and adding a hand trade, but the ‘textbook’ kata variation is done walking under the arm.
We used to do this technique spinning very fast under the arm but to spare uke’s arm we would have to loosen up and let the wrist slide. Now we execute this motion very slowly with a more compliant uke so that we can hold the hineri wrist position throughout the motion.
To me, this is the most painful of techniques when resisted. If I were going to develop ‘magical thinking’ about a technique (see yesterday’s post) this would be the one. But I’ve had Henry Copeland sensei burst my bubble about this technique too many times in randori for that. It is still awesome to me to see a good tori rotate his mass 360 degrees around a hineri wristlock at the end of an arm-length lever. The mechanical advantage for tori is impressive!