"what the hell were you doing when you subscribed to that feed in the first place" - the feeds I dropped were on two topics, but after reading them for a bit they were on the whole not about what they were meant to be about.

Yeah posts reappearing on RSS is a pain and it is not always down to the blogger, or at least the blog owner. When we put posts on the homepage here we sometimes forget to ask that they don't edit which causes republishing.