So what would you suggest? We could stop categories from being able to show up in other categories - that would neatly abolish the hierarchy. OTOH, many articles would end up with a ridiculous number of cats at the top (currently kept in check by the rough rule that if it's in a subcat, you don't put it in the cat as well).
No, what I meant is allow any arbitrary categorization scheme - sets can, after all, be inside other sets (or more than one set). A "related to" scheme rather than "is a". See "Continued" below
-- Chris Wood