Where are the darts

[Barb T]

...the apron edges will appear to be horizontal from waist to hip even if there's a significant taper

I assume that you mean that the apron edges will appear to be _vertical_ from the waist to hip??

In any event, the bigger the waist-hip differential, the bigger the taper has to be on the edges of the apron. You just can't successfully take it all up in the pleats, or would you want to. If you didn't taper the apron edges (i.e., the apron edge were square), the top of the apron would wrap way more than half way around the body, and the apron edge would no longer be vertical but would slant back toward the back of the kilt, even if someone has a very flat stomach (just try it with a bath towel, if you don't see what I mean). As viewed from the front or back, women are narrower at the waist than at the hips, rather than being built "square". So the outline of the apron needs to take this into account.

[Heming]

I assume that you mean that the apron edges will appear to be _vertical_ from the waist to hip??

Of course