"THE first time the Dow Jones Industrial Average hit 12,000, in October 2006, presenters on CNBC, a business channel, almost caught fire with excitement. When it reached that milestone again on February 1st the reaction was more muted, though the recovery from a low of 6,547 less than two years ago is remarkable, and soaring share prices reflect a corporate America that is leaner and stronger than it was back in 2006. The current profit-reporting season is shaping up to be one of the best ever. For non-financial firms in the S&P 500, earnings per share are now higher than they have been for at least a decade. With [...]