U.S. natural gas producers are slashing production in response to multi-year low prices. But they are also looking beyond the current slump, preparing to turn on more output by flexible operation of their inventory of wells. “Natural gas is currently pricing at or below costs of production,” an executive at an exploration and production company said in comments in the quarterly Dallas Fed Energy Survey released this week. Prices are historically low due to weak winter demand amid milder weather, record output…