gfk_velo, props to you. That was a truly masterful post, the whole thing I mean. I stand corrected on the FD indexing issue. On reflecting, I can see that yes, one sweep of the upshift lever will move the chain cleanly to the next larger ring only if the spacing between the rings matches what the shifter and derailleur are expecting. Our setup seems to meet this criterion "close enough" (in that we don't normally need to trim after a front shift, just a small click or 2 after several shifts on the rear as the chain moves laterally. I can see how, if the spacing was wrong and you had to fine-tune every shift it would be hard on the front shifter's innards.

Anyway, I learned a lot from reading your post. Thanks.
Les