I have been checking out the backlinks of competitor websites and found one of them had a huge pile of incoming links from what appeared to be spun content. Hundreds of pages each with a link constructed out of various combinations of the same paragraphs. In fact it was quite good - each paragraph made perfect sense and it was presented as a collection of hints on various web hosting topics. It wasn't until i saw some paragraphs twice after viewing half a dozen pages that I caught on. Anyway the pages were on a blog and the blog date indicated that the pages had all been written over the last few days. The backlinks though were much older. It sort of looked like there was a process continually rewriting the content around the same links all the time. What would have been going on here? Why would the pages be getting refreshed all the time? In terms of duplicate content when I did a plagarism check the same paragraphs were found all over the web so the rewrite would not have avoided this.