As a cynic, I believe that his twitter comments and the HMRC court case are not unconnected. By demonstrating that he is able to tweet freely, he is seeking to show that he is different from a 'normal' BBC employee and that he is entitled to have his salary paid to his personal service company, thus saving large amounts of tax. I also believe that the BBC will not take any action against him, as they also benefit from him being classed as a non-employee by not having to pay employer NI contributions.