I have noticed in the responses that people talk about a technique, say kotegaeshi, and everyone assumes its being done the same way. There are many names for Kotegaeshi, and it comes from the 2nd level of Aiki-Jujutsu techniques called Kotemawashi. What is most important about this is the term is just a descriptive title of the waza, not the way in which the waza is done. Depending on how the lock is applied many styles can have similar locks of differing names. One art I have studied takes kotegaeshi(outward wrist turn-kote maki-te hanna-kote-otoshi what ever you want to call it. Chin Na call the techniqe "white ape worships Buddah, yet they all are not done the same)and pins the elbow on the ground/mat and presses down on the wrist. It is indeed a form of Kotegaeshi. Another style I use calls this lock a Gosseneck lock, though my gooseneck is to the side. My point here is that we are dealing with semantics, and one can say they can get out of a certain technique based on its name, yet without seeing the technique, one can not say "I can reverse this or this doesn't work on me" All techniques that wind, say kotegaeshi, can be unwound, and you get Nikkyo(another Kote Mawashi-nikajo, wing lock-gakyu kote maki etc). It can be decptive to generalize techniques by name, versus their function. Aikido Nikkyo is mainly done with a 'z' shape of the arm. Most Aikido joint locks do not go bone to bone or attack the joint but rather go 'with' the joint. Our locks always go against the joint, or bone to bone. Our version of Nikkyo, called a 'wing lock'is done with both hands at the wrist, and taken straight down and brings the attacker into a knee. This is much different than my basic Nikkyo that I learned in Aiki. Chin Na applies pressure points, grabbing tendons, and a wringing motion to its locks, they look the same, but are entirely different, with different names. Once again I think its important not to get hung up on names of techniques, but more so HOW they are applied.