[rwh]

To have an "on plane" right forearm at impact, the right elbow will be bent.

You are right, of course. But I didn't "own" a feel that leads to those correct alignments.

I believe I was having some serious downstroke sequencing problems (6-M-1) in that release was initiating before my arms, right elbow and left hand passed line-of-sight-to-the-ball (6-B-1-C).

So, I had book knowledge, but I had not translated it to a feel that leads that leads to ownership and ability to repeat the swing. The feel that the right arm doesn’t straighten until past the ball appears to have corrected that (for me).