Twelve major shareholders in U.S. shale-oil-and-gas producers met this September in a Midtown Manhattan high-rise with a view of Times Square to discuss a common goal, getting those frackers to make money for a change . In the months since, shareholders have put the screws to shale executives in ways that are changing the financial calculus of hydraulic fracturing and could ripple through the global oil market. In the past decade, the shale-fracking revolution has made the U.S. the world’s largest oil-and-gas producer and reshaped markets . Yet shale has been a lousy bet for most investors. Since 2007, shares in an index of U.S. producers have fallen 31%, according to data provider FactSet, while the S&P 500 rose 80%. Energy companies in that time have spent $280 billion more than they generated from operations on shale investments, according to advisory […]