Part of this debate centers on the idea that in the visual arts it is hard to separate the artist from the work. The Mona Lisa represents not only the beguiling image of a woman, but the years of study that Da Vinci had put into the human anatomy, his mastery of imitating nature and an attention to detail found only through practice and patience. No one else could have produced that painting.
I don't think Warhol ever would have said he could have improved on Da Vinci's work. He knew whatever he did would be a Warhol, a completely different work in a different style with a different message. Perhaps he would have thought he could have created a portrait of the same woman that would have a different impact than the one that hangs in the Louvre, but that work would not be the Mona Lisa. And if Warhol did say he could improve it, it would be solely because that statement itself has the same kind of impact he sought in his actual work. The mere utterance of the thought would have been performance art to Warhol.
And the same concepts generally apply to Golden Age courses, the only difference being the non static nature of both the golf courses and how the game is played. We talk about Ross' Seminole and MacKenzie's Cypress. The hand of the creator is part and parcel of the ethos of these courses, yet we'll often quietly accept a few changes made in the name of improvement from time to time (would anyone complain if somehow Cypress added an 18th tee out on the rocks).
If paintings were "used" in some way other than being viewed, perhaps there would be an apt analogy between the worlds of fine art and golf. But they aren't. Yes, painters and architects may continue to tinker with their work over the years until they believe it is done, but you wouldn't alter a painting for any other reason.
Perhaps the better comparison would be between the world's of golf and architecture. Even the Louvre itself has seen its fair share of renovations.
Sven