It looks like Loathsxome's RSS flavour has a bug - new posts cause Google Reader to show all the posts as new (is there some UUID stuff missing?). So I thought I'd try the blog in another feed reader. NewsFire was the first Google hit, and so I downloaded it and fired it up.
The first thing NewsFire did was nag me to upgrade to Snow Leopard (no thanks). It comes helpfully preloaded with a bunch of feeds - e.g. the BBC seemed to be in there. Not wanting any of those I deleted them all - except the newsfirex.com blog. Delete wouldn't work.
Nonplussed, I quit the app, edited ~/Library/Preferences/org.xlife.NewsFire.plist, and removed the entry from the Feeds array. But NewsFire helpfully readded it.
plonk Into the trash it goes. I'm won't use software which displays such arrogance. Nobody should.