However, I have a question about duplicate content.
I understand how 5 levels can work on a forum:
Level 1: Index page Level 2: Categories Level 3: Sub categories Level 4: sub - sub categories Level 5: content pages
There is no duplicate content here because on the index, category, sub-category and sub-sub category pages there is no similar content. Most of the pages contain links to lower levels.
However, on a blog you can have the same post on the home page, the category page, the sub category page and the post page which is raging duplicate content.
I currently have no sub categories and have 'no follows' on the category and tag pages so that the posts only get indexed on the home page and the post pages, which now seems flawed after reading Brett's replies to the above post.
So how do you avoid raging duplicate content on a Wordpress blog in a vertical "themed" site structure as suggested in the post above?