Two things that helped me start to wrap my head around the wrist action (heh.)
DD on the Innova site talks about how the wrist should be like a hinge rather than a spring. Took me a while, but now I know what he means, and it's huge in avoiding "too much" wrist. It's timing, not explosiveness.
Hammer drills. They work. W/R/T the hit point and wrist, they overexaggerate the feel, and really help me to lock in the elusive feel of the hit point, and remind me that more strenuous effort in the motion isn't the answer.