Hya guys The wrist grab as a few have already mentioned was allegedly, supposed to stop the drawing of the sword. We will never know how often people pulled this technique off for sure, but i have used this in a calming situation. I have 6ft and 18stone so im a big guy. I have trained in a few grappling styles, judo, akido but it was the ju jitsu i had a lot of wrist lock usage as it was the longest i trained at in a grappling art. We used the wrist locks as party pieces mostly and demonstrated these to people when they did a famous request''''show me'''' Great break falls were used as we all used to do great high flipping rolling falls and land with a loud bang on the mat. These people where truly amazed. The situation i used it in was to stop 3 girls fighting each other. One had hold of a girls hair so that her knuckles were white, her grip was that hard, the other was sat on the pinned down girl. People tried to break it up and failed, i kindly applied an adapted wrist lock and lifted the girl out of the way via a lock on her wrist. I then released her to let the pinned down girl get away. There was no afters and people all got back onto their activities, drinking beer in pub This may possibly help to calm a situation like this. In a real fight, not a staged '''have this on yr wrist''' simply do not work to any effect in a violent attack on yr self. Their are too many things going on and the last thing on yr mind is doing and twist. I came to realize this as now i train at a cross training club. For my 1st degree i had to spar 32 rounds all differing in combat. Boxing vs kick, boxing vs grapple, grapple vs kick,,,wing chun vs boxing , and ground grappling. Real fights a wrist lock is sadly lacking, how many have thrown themselves into a breakfall to make the instructor look good eh? To rely on one is a fools folly. interesting topic