Woops forgot to add

Wrist grab defenses were originally significant to the Bushi to prevent their enemy immobolising the weapon hand and thus preventing the drawing of their Katana. Can you see a similarity with modern LEO's and firearms retention.

JKogas, you said it before I could, the clinch is the missing element that makes grabs of any kind a realistic and serious attack. As implied at the beginning of the thread, it's not all that common that an attacker will just assault you by grabbing an arm (though possible). It's in the midst of trying to defend yourself that your attacker or his sidekick will likely grab you.
Well said.

Sorry I didn't read all 16 pages of replies, so this may not be new.

Generally, people don't START o fight with a wristgrab, but when in a grappling/ grabbing situation (where both persons are struggling), when one person's hand comes free, he/she often attempts a close in strike. THAT is when the other person grabs the striking wrist (to prevent getting hit by that hand again).

Also, grabbing the wrist CAN be the biggest mistake one can make!

The thumb is the weak link in a wrist grab. Work against it either by using the other hand to help pull it free or using misdirection to pull against the thumb with a simultaneous punch to the chin with your free hand. You can also strike the thumb with a hammerfist or knifehand while pulling the trapped hand against the grabber's thumb. It's not astrophysics. Learning defenses against wrist grabs is a good way to work a beginner into the more salient aspects of grappling and grappling counters. It gives the beginner insight into how the hand works.

Oh and wristtwister I agree with the seibukan guy. He sounds like he has reality to back up his philosophies. Anyway your name is wristwister (did I forget a "t"?) or whatever. You do JJJ. That's how you learned your aikijutsu. Of course it's very important to you. I think Pat's take on it all is much more complex in it's simplicity. There is depth and efficiency enhanced by logic in his replies. There is over-specificity and narrow scope in your explanations.

IOW, Seibukan guy is spot on.

IMO...