Sorry to still be on this topic. The fit length looks good but for the shirt sleeve, would it appear of different length with vs without the coat on (espec barrel cuff unlike french cuff which is more "stabilised" at the wrist, for lack of better description)?
I understand what you mean. When you bespeak a shirt with a french cuff, the cuff isn't as snug as it is on a buttoned barrel cuff. Though, a tailor can adjust either cuff types to fit similarly, with a little more space for french cuffs. In fact, I had a shirt made up in Italy that utilises what is called a conical cuff (see picture below). The tapering of the cuff ensures that it's firmly anchored on the wrist and there's minimal movement.
The answer to your qn is that the cuffs should fit the same, and terminate at similar points, whether the coat is on or off. Though if your shirt is meant to be more trendy, and fashionable, you could always go with it fractionally shorter.
Shirts I wear with coats tend to be slightly more comfortable fitting, lighter-weight, and pricier.
I have another range of shirts, that I use a cheaper tailor for, that are slimmer (and so less long-lasting since you can't wear them if you put on too much weight). I also use cheaper fabrics for these. These, I wear without a coat. I find a slimmer cut on shirts, if I don't wear a coat, to look better.
