Timothy Walters Kleinert
Now, for hand shapes in particular, it seems too broad to discuss in general. I think it would be better to pick a technique and discuss just that.
Agreed. Lets discuss shomenuchi kotegaeshi (or any other one would be fine).
If the person attacks with with right arm, I tend to enter and pivot (as if I'm doing iriminage) - keeping vertical main with my spine. Then I would typically use my right hand palm up laying across their forearm giving them a bit of my body weight. My left hand would be between their shoulder and elbow palm on them. That arm would move be bending as I moved closer to them, and then I'd let my body weight start hitting them using that palm as a natural energy release of that movement (same as the hand on their neck for iriminage) except I'd let it slide down their arm a bit to get into kotegaeshi position. Then I roll that hand so more weight is on their arm nearer my thumb than my pinky as I continue to move into shikaku. When I roll back (move body weight neared my pink than thumb) I cut their center with my intention. I don't pay much attention to what my right hand is doing at that point. It's not cranking anything for darn sure. It just barely touches their finger tips usually. But I'm open to suggestions.
Maybe initial palm up should be replaced with wrist up, fingers down. Looking for inspiration..
How do I meet Howei Popkin? Does he do seminars?