At a private meeting in February, a group of environmentally minded investors were all set to battle with Mobil Corp. over global warming issues. Then Mobil floored them. Within economic limits, "a responsible company should reduce its emissions," Rob KIrchner, Mobil's vice president for environmental health and safety, told the Interfaith Centre on Corporate Responsibility, a group that coordinates investment policy for about $90 billion of religious pension-fund assets.