Probably toasty out here in the windy canyonlands compared to Boston, in the mid 20s F.

I wore my traditionally knife pleated 16 oz Strome (Macdonald of Kingsburgh) from Kathy's Kilts to work today. I was toasty too.

In fact, I forgot to put on my jacket when I went back to work after lunch, left it at home accidently. So tonight in the cold (I work til 9pm) I didn't have a jacket, but still, the kilt kept me toasty.

I imagine a box pleated kilt, given your research, would be even warmer.

Ron