Here's my history with respect to this subject. . . .
I have really really small bones. This translates to really really small wrists. So, before I started writing my own patterns, whenever I knit someone else's the fit on my wrists was sloppy. Add to this that I didn't know how to get sleeve length right, and you've got a mess on your hands. (No pun intended.)
So I learned long ago to make the wrists of my garments fit by doing the following:
- knit the front or back first;
- wrap the cast-on edge around my fist to find the minimum number of stitches that allows my hand to pass through;
- cast on this number of stitches for the start of my sleeve.
If the sleeve was 3/4 length, this method still served because (at least for me) the minimum number of stitches that allowed my hand to pass through was the same as the number of stitches that fit will on my arm at 3/4 length. If the sleeve was shorter than 3/4 length, I'd wrap a cast-on edge around my arm where and how I wanted the sleeve to start, and I'd cast on that number of stitches.
I just never trusted a pattern to know how skinny my wrists or arms were. (Both my arms and legs are pretty skinny . . . at least I assumed that because my wrists and legs are my arms would be too . . . maybe with gravity and age I should re-consider that assumption about my arms . . . okay, too much information.)
So this is what I teach in my classes--to not follow the pattern but to cast on the right number of stitches for you. And I'll remind everyone that this also works if you knit your sleeves down:you'll just use a bind-off row rather than a cast-on edge. It also, of course, works if you have thicker wrists, so cast on fewer stitches, then work fewer increases after the cuff or work your sleeve increases less rapidly as your progress up the sleeve.
Why is this so important--especially if we are competent at getting our sleeve lengths right? Because a sleeve that fits at the wrist is a lovely thing! But, more importantly, remember that the right number of stitches for your hand is also the right number of stitches for your arm at 3/4 length? So if you are having an I feel fat in my sweater day, you can push up your sleeves to expose the slim part of your arm (and the skinny girl under the sweater): your sleeve will stay there because you cast on the right number of stitches for it to do so!
Like shoulder width, this is not a suggestion that is part of our published patterns. As much of a proponent as I am, I don't address it in my patterns. It would make them too long and complex. What I'll do instead is talk about it up-front in any fit discussions--like the first chapter of MOTHER-DAUGHTER KNITS. And I always talk about it in drafting classes.
So isn't it wonderful that we have classes or forums like this to open this discussion?