Even with a 10.5 Stimp reading, balls were running off the greens into bunkers and collection areas. Once you got the ball on the green you were fine, it was getting the ball to stay on approach shots where the players had difficulty. The landing areas were literally 3-5 yard circles on some greens. The first hop on a lot of Rory's approach shots just bound forward like 5-10 yards and went off the back before the spin could kick in.

Typical PGA tour events usually run around 12. By comparison, if you've ever played Pebble Beach they set their greens to about 10-10.5 for the regular rounds which is perfectly fine and keeps play moving. But if they left it at that for next year's US Open the pros will destroy that course. So they'll ramp it up to 13-15 to protect the course from being embarrassed and brings scores closer to even par. Oakmont leaves their greens at around 13 or so for regular member/guest rounds but can go 13-15 for a US Open set up. Same thing, if Oakmont dropped their Stimp to 10.5 for the US Open the pros would go pretty low in scoring. Each course has it's own way of protecting par. Shinnecock didn't need fast greens to protect par. It's hard enough.