Here's my modified sleeve size if anyone's interested:
1. There are 90 rows from border to armholes.
2. Increases every 6 rows 6 times, then every 8 rows 5 times.

I can't remember when I was this excited about a project last: it's a thrill seeing it take shape in my hands.
The only thing I can't understand is Alice Starmore's tension! I don't knit particularly loosely (don't think I've ever had to change needle sizes to get the gauge called for) but in this case I get 24 instead of 28 stitches per 10 cm (4 in) even though I use thinner needles, 3 mm instead of 3.25 (US 2½ instead of 3).
I could go down one more size but feel the sweater will be too stiff for my taste if I do. Instead, I'm following the directions for a size smaller than I want - and it will still be a bit too big!
Now, I love Alice Starmore's designs and would love to meet her and thank her in person for everything I've learnt and been inspired by - but judging from her tension I would hardly let her massage my shoulders ;-)