Billy, thanks for the response! My apologies for taking so long to get back, I appreciate your quick response. I somehow missed the notification, then went on vacation, etc. :)

I'll continue to try to work the open F, as it sounds like it is useful to know.

You asked what I meant by "index finger twist," as that's where I'm having trouble. When fingering the open F, you need to do a "mini barre" with the index finger to hold down both the B and E strings. To make that work, according to Lisa's excellent lessons, you need to rotate your finger a bit so the bonier side of your finger is pushed against the fretboard. I find that pushing my ring finger against the D string, my middle finger against the G string, and then having to rotate my index finger to get the bone on the B and E strings is very hard on my hand / wrist. It hurts my hand a lot to get into that position. I feel it in the back of my hand, and down into my forearm.

Perhaps I should be doing some sort of stretching exercises?