Arne Duncan ended a week-long education and jobs stump speech bus tour in Chicago this week. And he had plenty to say about what is going on in his old stomping grounds at CPS. Some of what he had to say was undoubtedly music to the ears of the Chicago Teachers Union, given the weird and ugly battle brewing with the Emanuel administration (complete with a curious mix of F-bombs and hugs). Friday, he called for a doubling of teacher salaries nationally: