Taking in all input, I'm 2wks into my "hitter's one arm drill" practice. From a newbie, here are observations. 1) I've been previously suspicious that I've had "switter" tendencies encroaching. This drill has confirmed it by more easily defining the hitter's right side participation & control feel. 2) With the hitter's action so dependent on right-sideness controlling ... strengthening that side & building confidence toward that means has benefitted my swing. 3) Also, improper motions seemed to be amplified & so much easier to diagnose and correct.
As you can tell from my positive observations, I plan on continuing with the drill.