Jay,
I'll take them at your word that is the current status. They should and must work together. When that allows a course to hold both a US Open and a PGA Championship will be proof. It'd be interesting to see how comparative the course setups are.
In reference to what Ronald Montesanto said in an earlier reply
"Man, the day that St. Andrews as British Open venue (enough of this THE Open, as if it were the only one) determines what others can do is the day that...well, the day that I get angry. There is a piece on Herb Kohler (who owns half of St. Andrews, anyway) in Golf Digest, I think. He discusses "the Club Pro Championship is a great event" as the first communication between him and the PGA regarding Straits. Then, when they gave him the 2004 PGA, he said "that's a start...what about 2010, 2015 and the Ryder Cup in 2020?" This was when the USGA was still considering Straits for a US Open. Dye said, the course looks better in August and there is less rain than in June, so go with the PGA."
That is a good business practice for both the PGA and Mr. Kohler. Just pointing out that it may have had an unintended consequence in 2015, at least from my perspective. I remember media questioning why the R&A made no 2015 announcement when the Open concluded. I thought nothing of it then, saw the graphic today and wondered.
Just suprised that no one agrees this is a possibililty.