Having added CategoryWiki to various pages, I went back and tested it, only to find that the search also returned results for CategoryWikiEditing and CategoryWikiNavigation that someone else had added previously. It was then that I realised it would be possible to apply hierarchies to classification. CategoryWiki would return all pages relevant to the understanding and use of Wiki, with CategoryWikiNavigation providing a subset of those pages which offer more specific advice surrounding navigation techniques.
Clearly, this approach can be implemented for other categories, should the implementors be so inclined.
Unfortunately, this does not work any more.
See LikePages
The structure of the tree (or net) of categories should help in navigating. Pages belonging to subcategories should not be listed in one list together with the pages belonging to the top-level category. -- HelmutEnckRadana
See SubCategories