Re: Pain in aikido?
I've always been taught that pain is not necessary for proper aikido technique execution - "all" that is required is to control uke through the use of off-balance (if only that was as easy as it sounds!). Joint locks are there to provide a better connection to uke's center - so even techniques like kotegaishi can be performed without pain compliance.
Another thing I've read and have been taught is that the onset of pain indicates that damage is occuring or about to occur. Further confirming this concept is that most dojos don't allow children to receive any sort of locks - exactly because they don't detect pain until the damage is already done. I don't want to damage my training partners.
Lastly, if involved in a situation on the street, your attackers adrenaline could easily prevent him from feeling much pain until everything is already over with. I don't want to train in the dojo to rely on pain compliance, if pain compliance very well may not work on the street.
Having said all of that, unexperienced ukes often push back against various joint locks and cause themselves pain. Our solution to that is to go slow - which one needs to do anyway to insure uke is off-balance at ALL times during a technique.