Since this is the only thread that seems to be still functional, I guess I'll add my questions/comments here. All subsequent quotes are from Mr. Kabbaz's tome.
But, as the PR truthfully says, the Gusset really adds strength.
It seems like every shirt manufacturer who uses this feature makes the claim about strength, and I've never understood it. I've never seen a shirt side seam fail, with or without the gusset. I can't imagine that that would be anywhere close to the most vulnerable area of the shirt. If you're having trouble with the side seams failing, what are you doing? Wearing the shirt to play rugby? I have to say, though, that I like the way the gusset looks. It may cover up inferior construction, and it may be completely non-functional. But I do think that it looks good for all its worthlesness.
The sewing 'foot' used to make the hem is called a "scroll foot". Its action is to roll under a small portion of fabric into a finished edge while placing a stitch designed to hold the rolled fabric in place. It is a very difficult foot to use and requires years of practice to master.
Do you have a picture of this foot that you can post? I'm having difficulty visualizing it. What's your philosophy about the design of the tails of the shirts? Looking at the picture of the pattern, it seems like your tails (or at least the tails of this particular shirt) are the typical American swallow-tail design and not as deep as those that you find on some of the British and Italian shirts. What do you think of Charvet's square-tail design? They claim that it tucks more neatly. I don't know about that, but it certainly looks cool. About fabric's country of origin: I've seen a lot written here and elsewhere that the quality of textiles from China, Japan, and other countries is steadily improving, to the point that some Italian mills are having difficulty justifying their higher prices on the basis of quality differences. What would have to happen for you to consider using fabric from mills other than in Switzerland and Italy? Thanks again for the essay, Mr. Kabbaz. It was very interesting and informative.