An extended version of the Commons sorting scheme logic regarding over-categorisation, which also clarifies that it is acceptable to link down via two different paths. Addition of the "A", "B"... letters makes it easier to discuss the logic with a user who gets the system explained to him/her.
<a href="//commons.wikimedia.org/wiki/User:Ingolfson" title="User:Ingolfson">Ingolfson</a>
2009-01-24
Own work, modified from <a href="//commons.wikimedia.org/wiki/File:Over-categorization.svg" title="File:Over-categorization.svg">File:Over-categorization.svg</a>