Of all the economic establishment he is more likely to tell the truth or at least the truth as he sees it than any politician right or left.
He has a professional reputation to maintain, so if he sees signs of optimism, it is a good thing, he would also be man enough to admit when he is wrong. Also in that statement is an admission that the bank was too slow to react to the financial crisis.
He has no political axe to grind, been there for both parties, he is effect the nations health doctor. He speaks a lot of sense and i very much doubt if Joe or Joanne could get close to what he is saying