Armhole shaping at last

One thing my husband and I have in common is a love for the look of fine gauge knitting, so the sweater that I began for him late last summer is on 3.0mm needles, out of Louet gems. I love the feel of the wool, but it's not the most evenly spun--there are fuzzies every so often, and sometimes it's thicker, sometimes thinner. I'm hoping because it's so fine, no one will notice the differences in thickness, and after it's blocked, I'll try to work the fuzzies to the back. (If you click on the image to see the larger version, on the lower left, you can see a rather large fuzzy.) Now that I'm ready to do the armhole shaping, you can really see the ribbing pattern; from one edge to the other, the number of stitches is:
10,11,12,11,12,11,12,11,12,11,10.

So far the pattern has been easy to follow, which I've heard is unusual for a vintage pattern; it doesn't seem to assume any special knitting expertise. Finding a suitable yarn was a challenge, though, since I couldn't find any information anywhere on the original yarn's yardage per ounce, and it took a lot of swatching to get the correct gauge. I didn't set out wanting to knit from a vintage pattern, but we had no choice--we couldn't find any contemporary men's patterns that were both in a fine gauge and for a 38" chest. It seems that all the men nowadays besides mine are large, like a loose fit in their sweaters, and want them knit from worsted or chunky yarn.