"Techniques" change over time. That's the kind of thing I would prefer to learn in person from actual instructors, who are actively doing the kinds of dives I want to do. The underlying principles, such as the physiology of decompression, don't change.I have considered it! It would be a book I got after this one, as I would like one that's focused on techniques and the like, but it's definetely one to cosider. Technical Diving: An Introduction is a good recommendation though!