I wanted to make a robe for a friend and I figured I'd use the same pattern I'd used to make my robe. Since I was making a different size and she is short, I decided to make a muslin. Before I made it, I chopped 4 inches off the length of the front/back and the sleeves (because on mine the sleeves are way too long).
When she tried on the muslin, the sleeves were still an inch too long. The front hiked up above the horizontal line I'd drawn for fitting, indicating the need for a full-bust adjustment. I mean, it's just a robe, but an XL with no dart? They go to the trouble of making you cut and sew a two-part sleeve, but the fit of the overall robe is terrible. What surprised me was how voluminous the sleeves were. It was insane. plus, they are very low, and I worried it would restrict arm movement, especially when I narrowed the sleeves.
So I cut another inch off the sleeve length and narrowed the top of the sleeves 2 inches and the underside another 1.5 inches. I also added a dart and did an FBA of 1 inch. Unfortunately, I was too lazy to raise the armhole after all that.
Then I sewed it up in a flannel print she'd purchased, added some satiny lining fabric for trim, and voila, fits pretty nice, looks pretty cute.