I have been trying to find the time to post this, because I have been doing some actual white shirt sewing.
First of all here are the sleeves - full, but 3/4 gathered sleeves on a band.
I am pretty pleased with them and they will look even better on the shirt I imagine. I used a technique a sewer shared with me in a class for the gathering - so obvious everyone in the world but me was probably already doing it.
Rather than pull up and adjust the gathers into the band - you know all that repinning and adjusting you usually do? I measured the band and then gathered and perfected the gathers to that measurement and basted the gathers in place and then pinned it to the band.
Seems obvious to work to measurement not pin to the opening but this was new to me.
I do the same thing when I ease in a sleeve now, measure, adjust the gathers, and steam the sleeve cap over the end of the ironing board, getting rid of all those potential little puckery things, before I even think of pinning it into the armhole. So much easier than pinning, stitching and then trying to unpick the pleats or trying to press them into invisibility after the sleeve has been stitched into the armhole.