Stephen Skinner is known first for popular books. He wrote on feng shui from the 1970s, at a point when almost nothing on the subject was available in English, and his early collaboration with Francis King produced a practical handbook of ritual magic that shaped how a generation used Golden Dawn material outside any order. He also worked on geomancy, the divinatory system in which sixteen figures are generated from marks made at random and read through a chart, tracing it as a historical practice with an Arabic origin in the science of the sand and a documented route into medieval and Renaissance Europe, rather than presenting it as timeless.
That historical instinct is what separates the work from most of the shelf it sits on. A popular book on a divinatory system usually presents the system as received and complete, with no account of when its parts were assembled or by whom, and a reader has no way to tell a fifteenth century element from a twentieth century one. Treating the technique as something that has a history, with sources that can be named and dated, is a different undertaking, and it is the reason the atlas can cite this material at all.
The popular books carry the usual caution that applies to any introduction written for a general market. They simplify, they present a working version of a system rather than a survey of its variants, and in the case of feng shui they entered an English speaking market that had no way to judge them against the Chinese literature. The atlas cites the popular titles for what they demonstrably did, which is to introduce a subject, and cites the editions and the historical work for claims about what the sources say.