What is wrong with a par 70 6500yds with a slope of 142
There is nothing wrong...but...
Sadly, a golf course of those dimensions, regardless how great it is, has ZERO chance of ever holding another US Open.
Even though 3 of the par 3's can now play over 210 yards, they all play actual club yardage quite differently. Although # 9 can be stretched to 210-215, it plays significantly shorter due to the downhill tee shot. For the top players, it is at most a mid-iron shot, 5-6 iron. The interesting thing about Merion is that even before this added length, it always played longer than its 6600 yds.
With the routing being as it is, it just turned out that the shorter par 4 holes at Merion could not be lengthened due to the property borders, and the only place there was room to expand, happened to be on the already difficult longer holes.
**Thanks TEPaul. I thought the new yardage at Merion was about 7000. I do know for a fact that the new back tee yardage at PVGC is now 6999 yds.