A Zeppelin knot isn't any harder to remember how to tie than a butterfly knot... if you know you know, if you don't then you don't. A butterfly works well for loops in the middle of a cord because you don't need access to the ends of the cord to tie it. But it slipped for me on a hammock suspension line when I tried to use as an attachment point for a removable ridgeline for a bugnet (and no, there was nothing attached to the butterfly loop when they slipped).

AmSteel is very slippery and it doesn't work well with a lot of knots that more traditional rope does.