I was reading a post from a blogger who had recently been Google slapped. He listed out all the proper things that he did, including...
"I avoid duplicate content by properly by using nofollow on my archive links"
How can my archives be seen as duplicate content?
Are there other internal links/content that could be negatively impacting my blog's ranking?
I think that I am just missing an obvious point here. I thought the nofollow was just so that folks can't benefit from me via comment spam. I did not know that it should also be used avoid a negative impact of my own work.
Nofollow can be used for any link you don't want the search engines to follow. It can be for comment spam, but it can also be for other reasons as well. Using it to block duplicate content is one such example.