"The masses would perceive it as substandard."
That depends on where you are! Can anyone here recall anyone coming back from Sand Hills or Bandon Dunes and complaining about the "substandard" turf? [I've only heard it once or twice, and it was from someone who was emphatic before they saw the course about fescue being the wrong choice.]
I think the fescue works better at Sand Hills and Bandon Dunes because they're isolated, and there's nothing else to compare them to. On the other hand, when High Pointe was practically across the street from The Bear, or Spanish Bay from Pebble, or Whistling Straits from Blackwolf Run, and when the green fees are high, the paying customer wants to know why they didn't use the "better" turf next door.
Fescue will work in heat [I've seen the Sand Hills when it's 100] or humidity [not many dry days in the U.K.], but not heat AND humidity. It's also not worth a crap unless the soil is truly sandy, and I'm not sure the soils at Whistling Straits were suitable. But, I still think they should mow it tighter and see. If it doesn't hold out, then overseed it with bent like everyone else wants them to.
RJ: One of the most brilliant decisions they made at Wild Horse was how to grass the place. They used the bluegrass fairway mix you discussed to address divot-healing concerns, but switched to fescue 30-40 yards in front of the greens, so you can play all the links shots around the greens which I talked about.