Thanks for the thoughts, David.
I can assure that if you saw the 6th at Oakmont in person, you would certainly say it took guts to build a par 3 with such a strongly sloping green, guarded by such severe bunkers, and a stern test for a mid iron. And yet it's not over the top, at least imho.
Likewise, the 8th is certainly a stern test. The green looks like a sliver from the tee, and appears to be fronted by a large bunker. Then when you get to the green, you see the bunker which appears to front the green in fact has a great deal of approach area behind it, certainly allows the running shot (as do Oakmont's maintenance practice, hat tip to the crew).
Again, I'm not trying to rip anyone, nor am I trying to criticise the Riv's terrific set of par 3s or even say Oakmont's are as good or better. I just happen to believe Oakmont's par 3s are darn near as good as it's magical par 4s and 5s, and I'd really love to hear the reasoning behind anyone claiming otherwise. It's not enough to me to just say they don't stand out as particularly memorable or whatever.