It's probably heresy..... but I've never basted the pleats on any of my wool kilts before pressing them with a steam iron, and I've always had a good result. The main reason for not basting is that it's usually only a few pleats that need crisping up after I've been sitting on a kilt that's still wet from the rain. I've found that using good quality iron & pressing each section heavily, rather than running the iron over the fabric tends to work well.

Flak-jacket on....