I noticed recently that a lot of the time comments would be repeated, twice, maybe three times quite often. It puzzled me for quite a while why this was happening.

Then I posted a comment myself the other day and realised what was happening. My ever reliable web host (well, you can rely on them to ensure things that did work don't continue to work) was not processing a piece of code as it had done before, which meant when a comment was posted, an error screen appeared. So I figure users were seeing the error, using the back button and posting again. Despite the error, the comments were being posted.

I've sorted that out now so hopefully no more repeat comments!