It kind of seems to me like, if categories are exclusive, then there should be some kind of chronological link between things in the same category? Maybe my mental models are all wrong here, or maybe this is a theme thing and I need to do it myself. One sec.
Still here? Cool. It looks like this is something I'll have to write myself. Good thing I was planning to put together my own theme anyway. (It doesn't really matter how computationally intensive the result is, because it only has to run on my machine.)
I have various things I'm planning to put on this site (like, somehow, I'm going to publish the One Man Institute of Inapplicable Physics), and I think probably they ought to just be published as blog posts. I'll see how that all works out.