I left this paragraph as a comment in reply to this blog post by Fred.
You have said a few times that you could not do your work without your blog. That is the best rationale I have seen for your daily blogging. True for me as well. My blogging is integral to my work. I am early stage, so I am even more dependent. Blogging is also like working out for the mind. It feels like doing push ups and is great fun. Blogging is one of my favorite things to do online. I would be a less intense consumer of content if I had not been an avid blogger.