Small circles - all in the wrist?

In a previous post -- Ways to Push and Pull -- I showed a clip of Professor Wally Jay -- founder of Small-Circle Jujitsu --  inflicting impressive pain through a range of joint-locks at the impressive age of 70 on a variety of strong young men.  Here's another (shorter) clip of an even older Professor Jay dishing it out:

In the previous post I mentioned that Professor Jay emphasizes a wrist action similar to how you would turn off a tap; it combines push and pull.  One of my students -- Hi Lejoe! -- asked me whether that was all there is to it: Is it all in the wrist-action?  My short answer was: "No, there's more to it than that".   There usually is.

The push-pull wrist action is important, but not enough.  I showed Lejoe a lock using the wrist-action by itself -- a little unpleasant, but quite resistible -- and then I did it again, but added a missing ingredient: A small weight-drop.  The result?  Instant compliance (and belief).

I think that the wrist action must be present in small-circle techniques to create the small circle, but other movements and principles contribute.  In other words, the wrist action is necessary, but not sufficient.  The other components may need to be switched in or out depending on the technique and situation.  For example: In the clip there are times when Professor Jay lifts or twists rather than drops.  

More broadly, push and pull are part of the story, but just a part.  Even when something works, maybe it can be improved: Made more efficient, more effective against other opponents, and so on.