jurasketu

Tap early and often is my motto. Even just applying wrist locks "properly" without extra mustard can really hurt - so you have to be careful and be sure to complain to your partner when they over apply. If they dismiss your concerns - don't work with them until they fix their ego. This is practice not punishment. Controls should always be applied carefully and slowly so that uke has a chance to feel the control and tap before harm.

Pain compliance style controls are likely poor training technique anyway. Untrained people won't know how to avoid the pain and will thrash around probably disrupting the control or breaking something and still escaping the control. The control should be a control - not a pain compliance.

This is really important when working with children. Youngsters' growth plates can be damaged by "ordinary" controls. Children will often refuse to tap to prove technique doesn't work. So will newbie adults. Ego needs to be set aside in favor of safety. I never apply controls to children or newbies to prove it works. They trust me to NOT hurt them. I consider it my solemn duty to not hurt them. Accidental injuries happen often enough. There is no reason to make them happen.