The WordPress SEO Plugin by Yoast is a wonderful plugin for all practical purposes. However its got a minor glitch (or feature – depends on how you perceive it) that it adds extra columns to all post listings. Removing them is easy, but not many people venture into that part of WordPress – The Screen Options. Unselect the columns corresponding to WordPress SEO in screen options so that you don’t have to see them in post listings again. Screenshot Below