And please don't confuse a sewn down and tapered Fell with edge stitching along the edge of each pleat.
Each pleat edge will have a line of machine stitching along its length about 1/8" away from the edge.
This is necessary on Cotton and Cotton blend fabrics because they will not hold a crease as well as Wool. Some companies top stitch only on the outside of the pleat and some do both the "out-pleat" and "in-pleat".