BertMcG:

Some years ago, I had a Smith tartan kilt pleated to the red stripe. It's a large sett, and I ended up with 18-19 pleats that are as deep as you'd described. I love the kilt, but it's heavy. It doesn't swing quite as well as other kilts I have with shallower pleats, but it's not bad.

Curious to see what the kiltmakers will have to say on the subject.

SM