I love it so much, everything that wasn't quite perfect about the first version has been carefully re-worked and I'm delighted with the results. It looks better and it was simpler and more fun to knit. Plus I was being good and pattern writing as I went, so no awkward reverse engineering.
The yarn is an undyed alpaca silk blend from UK Alpaca, I used 4 100g balls. Need to email the company about the yardage though, since it's not on the bands or the website* It is beautiful though and I was careful to incorporate the fact that it stretches considerably in length into the pattern. Slightly strange to knit something that looks too squat but I forced myself to trust the swatch + maths and it sighed with relief when I measured it after dunking in the sink. I think it's precisely this lack of memory that will create the perfect drape for this pattern, the bamboo soft I used for the first version did the same (much to my annoyance since I hadn't taken it into account!). It's just 'wooly' enough though to give the smocking a wonderful depth and definition.
* I got a response - a 100g ball is approximately 265 metres and the 50g balls 132 metres.