Originally Posted by kiki
Major status for Dallas and Masters was earned because they were Circuit end Championships, like a big playoff, while Phily was just a very important stop on the regular tour, and specially indoors...
But being a circuit-ending championship is not the same thing as being a major. Today's Masters Cup is certainly not among the majors. The 1970 Dunlop Open, like Philadelphia, was not a circuit-ender, just a very important stop on the tour.
Think of it this way, there were many years in which both the WCT finals and the Masters took place. In some years you can include one of them as the fourth most important tournament of the year, and perhaps call it a major. But Dallas and the Masters can't be considered majors every time they were held, because that would leave many years with more than 4 majors. And that just creates major problems, no pun intended.