The other takeaway is quite possibly that my theme sucks. Any little thing that wants to be wider than the sidebar gets its way, despite my protestations. I did not design this whole theme myself — I just heavily modified an existing one. I might consider switching, but I really love the look of this theme and want to keep it.
I’m wavering between dusting off my web design skills and just whacking this theme into shape, finding something similar but better coded, or just calling Stephanie Leary and offering to pay her to do it right from the ground up.