Org-mode allows marking a set of tags as mutually exclusive. It also allows the inheritance of tags.
(from now on I am talking only about these mutually exclusive tags) When a tag is set in a parent, but also in a child, what I expect to happen is that the child is not included in searches/selections with the parent tag. In the example , a search for black (e.g. C-/ m black <ret>) should not match poodle, because it is white. Now I realize that the mutually exclusive tag concept is probably only a convenience for adding tags with C-c. And it doesn't seem to have any other implications, but it would be nice to have. Do you think this is a possibility or that I could get this behaviour some other way? Thanks!  http://paste.lisp.org/+76JF