Seems like a good resource. Interesting read even as a single/non-practicing bottom, lol. Includes a lot of practical information beyond simple "Stay safe and have fun" that resources online etc sometimes boil down to: types of rope and where to buy them, types of knots, how to tie what part of the body for different restraint levels, and so on. The author consulted a range of disciplines with relevant knowledge, from military restraint techniques to camping or boating knots to medical papers, and brought them all together here.