I just wanted to let the people using the RSS feed know that I am aware of the spurious posts in the feed. I have a plugin which is supposed to prevent the posts from showing up in your reader, and it is clearly not working.
Actually, it's more complicated than that. The main blog feed goes out through 2 sources, and only one is broken. If you haven't seen any extra posts, it's because you're getting the feed that is not broken.
Here's the feed that is working correctly:
I am trying to fix this problem (and have been for several days), but so far my efforts have been fruitless. If this really annoys you then you might want to subscribe to the feed that isn't broken.