That is entirely up to you! Do you perhaps want to have your say on something, without your co-workers recognising you? Maybe you have something explosive to report. Or does your alter ego need a place to exercise? It's much the same... whether you do it at the time you are creating your blog or you do it later, the option is there for you to specify whether you blog under your DocCheck profile or anonymously. This is equally true for each of your posts.