By Mark Kleinman Mark Kleinman is Sky News’ City Editor and is the man who gets the Square Mile talking in his weekly City A.M. column. This week he tackles splashy Telegraph stories, Legal & General’s spring cleaning and the tax hike fears Black comeback would be a tall Telegraph taleHold the front page: do comebacks arrive any more startlingly than this? Lord Black of Crossharbour, previously known as plain oldConrad Black, cannot have harboured much hope of returning one day to The Daily Telegraph during his dark days of incarceration. Whether he does or not is still an open question, but t…