When I lay my kilts out flat to iron, they create a semi-circle due to the taper, but I can still ensure that the pleats from teh fell down are parallel, and iron accordingly w/o creating the curtain effect.

But I can also wear the same kilt day after day with little or no noticeable wrinkling, because I take good care as to how I sit on it. Thre are several threads and a good video by Hamish on the subject, and it beats basting and ironing hands down.

If I need to iron more than once a year it's unusual.