It would seem that for a good fit, the underkilt/protector would have to hang similarly to the way that the kilt hangs, that is, with pleats in the rear. Otherwise, don't the kilt's pleats drag on the undergarment and interfere with the swing of the pleats? Also, I would guess that sitting, getting up, and performing other activities while wearing two kilts/unbifurcated garments of two different shapes on top of each other would cause problems such as bunching up, or hanging awry. Am I wrong?