Much of this "opening up" hoopla, according to a friend whose information I trust, was started by a guy named Jim Benjamin back in the 90's. "A pipe repairer by trade, he convinced people that the draw on pipes was too narrow. He would drill them out and people were convinced that he had done something miraculous. It grew from there.". I think the attention paid to the drilling and finishing (smoothing) of the airway, in both the shank and stem more beneficial than enlarging them.