Blog posts can be the ultimate rough draft for any project. You could potentially write a paper on a blog post, and then ask for editing advice, or technical writing advice from people around the world. It is a medium that needs no backspace or copy paste. You can effectively write out your paper, read it aloud to yourself, and then use notes and your blog post to write your paper. It's a kind of way to get more than you own input on the editing of your paper. Like the difference between a group project, and individual projects. Other people might see your words differently than you intended, and allowing them to be read in a blog post before the paper is due, could potentially save you some trouble in the end.