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I would think so. Aren't you committed to your first layer as well? I would assume the highlights and such have to be put down first as you are building backwards on the glass? Or maybe I don't completely understand it? Anyway, it is a very successful result and I love the blue colour story.

You are right, one does work in an odd sequence and the highlights have to be put down at an early stage. I also work with leaving areas blank, like in watercolor...