There is nothing questionable at all about why OPEC ramped up production. Fracking and other advanced recovery techniques in the U.S. and the potential of Canadian shale oil meant that the U.S. could produce enough oil to cut OPEC out of the picture, so long as prices were high. These aren't cheap technologies to implement.
So the Saudis stepped up production to lower prices and drive American competitors out of business. And yes, this is really pinching Saudi incomes. My heart bleeds. Cheap OPEC oil may have made the Keystone pipeline irrelevant, but the Saudi's are a long way from killing the U.S. production industry, even if they have hurt it badly, and when the Saudi's finally cave to pressure to raise prices again, I think they will be surprised to see how quickly U.S. production rebounds. Life in the Oil Patch is always a continual Boom/Bust cycle, and people in the business learn to deal with it.