I was curious about how those formed as well. I noted that even in front of the green, they appeared smoothed out probably by mowers, so its not an ongoing phenomena. Hey, I never said to take it out, just that I wouldn't design it and I would actually leave it, especially if its a national treasure.
Maybe I will try to design it, so I'll fire up my CAD system, try to replicate those contours exactly so I can plop it right in my next production house design. And, since I work mostly in clay soils, I will put a small catch basin in all of those little holes and make the Guiness Book of World Records for "Most Catch Basins in One Fairway."
I will be away from this site for a while trying to calculate the gradient of all those drain pipes.......