I am currently double coating my albumen prints-- hardening the initial coat of albumen with an iron before the second coat. However, I still sporadically get bubbling/blistering and figure it's somewhat unavoidable when using albumen... I am wondering if I can replace the initial coat of albumen with, say, arrow-root (followed by the albumen coat) and still have the benefit of increased dmax? I figure this could also prevent the blistering... Does anyone have experience doing this?