Hi Martin,
I always thought they had some work done, but in my several plays over there, I just figured it was master plan-type work. They have done the tree clearing, bunker-maintenance, and remowing the greens to their original edges that many Golden Age clubs have done in the last few years. I think much of it was in relation to the hosting of the Senior Open in 2001. Interestingly enough, the winterkill from the 00-01 winter almost killed all of their greens only a couple months before the tournament.
The biggest "change" I saw last year was the addition of an additional irrigation pond behind the 3rd green, altering the view quite a bit. Other than that, I don't think the course hasn't been altered much.