Hmmm. I'm as far from being an expert as anybody can be, but, for what I read, 0% superfat is a no-no.
So far, I've made 2 batches of soap and, as you know, the last one wasn't that great, but I've used both of them for my hair, and they both felt great, and left my hair really clean. Both batches had a 5% superfat.
Then again, my hair is about 1/4 inch long, so I may not be the best example to follow... :wink: