Clap off. I'd been trying to finish this in time for Maryland Sheep & Wool, but ended up working on it there instead. I've decided it was meant to be a Mother's Day present to myself; I've been dragging it off the shelf and forcing it to hug me all day.
Notes: Knitting to pattern on a US 7 needle, I ended up using six skeins of Grignasco Top Print (sport weight alpaca, Colorway: Berry), about 660 yards. Final dimensions: approx. 19" wide x 66" long--longer than I thought, which is fine.
The end result is worth it, but it's quite a slog. Definitely get a hold of Soul Knitting's Clapotis Spreadsheet; checking off the rows as you go is most encouraging.
When measuring knit side up from the cast-on, the right side is the width, the left side is the length.
Rule of 5 for yarn amounts: you'll use approximately 1/5 of your yarn for the increase section, 3/5 for the straight section, 1/5 for the decrease section.
As you slog along, watch for the following change-ups: Section 3, Row 6 (ssk, place marker, yo, kfb). Row 8 is when you get to make your ladder (yay!). In Section 4, there are ladders at the beginning and end of Row 8 (yay! yay!). Remember you're only working through Row 10 on the 8th repeat. In Section 5, Row 2 should begin with a Purl 1 (a mistake on the version of the spreadsheet I used; it might have been fixed by now).
I chose not to block; I like the curls and squiggles.
Onward to some palate clearing warshrags before I cast on my next one.