.. An excellent suggestion and observation. Having examined a few period clothing articles much credit and skill has to be given to the "old way" of sewing items. A few years ago I was checking over a gentlemans undershirt that dated to the late 1840 early 1850 era. Even on such a common item the stitching was was so fine and difficult to see. Stitch count was about 20 per inch.
On flags Ive seen the stars sewn on crudely with raw edges left in place. Some just whip stitched, Then others finely stitched and delicately tucked under while still maintaining a sharp even outline of the star. One of the interesting items I find is the ability to sew on the stars on both sides at once, equally tucked and hardly visible. Thats some skill!...