I've a few inches to go on the rather heavy sleeves and I think I need to rip them out. They're far too wide for my skinny armed brother.
Despite the fact that I did actually swatch for this, I'm still unsure of what actual size to knit so I'll recheck the gauge on the (nearly finished) sleeves and go from there.
I got him to measure the length of his arm last night, 20 inches, which in the pattern is the extra large size, but the length of his back is the small size. See, problems all round.
I'll see what happens.