A bunch of electronic cards without a vague category link to them has no value. If you don't classify your information your information is worth zero. The page's place in the outline will probably mean more than all the words written on that page. Ask librarians if an unclassified book has a value! Some people on the Internet have forgotten to keep the great aspects of the library classification system. All wikis are doing is create more and more dump. Not a consistent body of work.
The modern paradigm the Google, Yahoo paradigm is not a model to copy. With billions of pages on internet they had no choice than to follow this hyperlink paradigm. However, with a few thousand Wiki pages, complete categorization is possible, giving a meaning to this mass of unsorted pages. Without categories, we just create and create more mess and our work becomes less and less valuable because it is scattered.
Some people will create content without considering its category. Thus, to enforce your objective technically, you must either:
But social solutions also work: you could get the collective to quickly categorise the new content (or at least add it to CategoryUncategorised) as part of their housekeeping work. If ColdBlanket was spoiling for a fight, she could even mark such new pages as "DeletedPage - uncategorised", but that's not fun. More importantly, it should become a CommunityExpectation that the creator of a new page creates it in a category. At root, this is all that we need.
CategoryUncategorised is of course a hack - logically, the page is still uncategorised. However, it is an easy way to create and maintain a list of uncategorised pages, so they hopefully don't get forgotten.
The problem with our era is people think computer solutions are the panacea and the answer to everything - eg AutomaticCategorization?, ReverseIndex. This is wrong! There are certain tasks which are better when they are created by hand using the human brain. Like this Road map system for example.