Directions on the Viking knit are fine, directions on the projects do not have step by step diagrams, or really broken down steps. Feels more like a summary than directions.
The chainmail instructions also seemed lack lustre. I've had good teachers in the past and this added nothing.
Honestly, for Viking Knit I'd say to look for a youtube tutorial. For Byzantine mail check out David Scott Plumlee's Handcrafting Chain and Bead Jewelry, for other patterns check out mailleartisans.org - much better step by step pictures. (Especially for what this calls snake chain, AKA half Persian 4-1, which is gorgeous, but brutal.)
Excellent instructions on Viking Wire Weaving. I love that this book rates the projects from 1 to 4 "vikings" according to difficulty. I would highly recommend this book to anyone wishing to learn this easy jewelry-making technique.