It is almost exactly two years since the now outgoing Director-General, Mark Thompson, admitted on 1st September 2010 that the Corporation had had a 'massive Left-wing bias', with a particular animus against Mrs Thatcher.He rather spoiled his Mea Culpa in the next breath, however, by unconvincingly claiming that such a bias was a thing of the past and that during his watch the Beeb had miraculousl