OK. I *think* I am finally:
A) getting a good grasp of how each part of this pattern works;
B) getting OK at noticing where I've made a mistake;
C) (related to A) getting decent at remembering where I am in the pattern, and when I need to switch modes.
I am *almost* to the point that I kept stumbling over last try. And comparing that attempt to the one under way, I think I know where I went wrong before and how that hecked everything up.
Slow but steady progress!