I suppose it was time for a new template anyway, but I’m not really feeling like organizing that now, so for the next few days at least, the sidebar is going to be missing on my main blog page. Which is a crappy solution, but it’s all I’ve got for you right now.
UPDATE (the next afternoon): Okay, so it totally wasn’t the fault of the plugin: it was some stray div tags that got into the post because I copied and pasted HTML into the Visual Editor. Now I know better. It’s a dreadfully newbie error, I suppose, but it’s never happened before, so I didn’t even think of the possibility.
And I should add that the plugin I thought was at fault is a very cool one for WordPress, by the way: Simple Exclude lets you quietly, simply exclude posts from specific categories from the front page, archives, searches, and RSS feed of your website. And since it also won’t screw up your website unless you screw up and stupidly include someone else’s div tags in your content, I can highly recommend it. The plugin is here.
Kudos to Paul Menard, the plugin author, who was very nice as I freaked out and blamed his code for things it couldn’t possibly have been doing.