I have seen this in other feeds occasionally as well.  It appears to be a 'feature' of Google reader.  If I understand it correctly, it appears that if an item in the feed is modified you will see both the original version and the updated version as separate items.

You can even see it if you look at the two RRD posts, they have a different timestamp, and if you open them you will see slightly different body.

So the simple fix would be for Kyle/George to never make any errors and post a perfect version the first time.  :p