This is fascinating. It reminds me of what director Frank Capra said about his early years with the talkies, when sound had first come to the movies. If you look at his films from the early to mid 1930s, you can see and hear what a jump up/improvement Capra made -- everything in his films (sound, movement, pacing etc) seems so much more natural than that of most of his contemporaries. Capra said he realized early on that there was something about the movie watching-listening experience, i.e. about being part of the audience, that seemed to make everything slow down and feel stilted to an audience. And so to counteract that, Capra made sure that everything sped up on set, while filming - he had his actors move around more quickly than 'normal', had them speaking/saying their lines faster than they would 'in real life', and that ended up having his characters/films seem so much more natural to the audience.
Don's point about allowing for the process of softening that comes with grassing and with time struck me as somewhat analogous. It's as if, with the always developing construction technology available, many architects and their associates didn't/don't allow for this process or even recognize it, and so they smoothed everything out (all the edginess and abruptness) too early, before the grassing -- which meant that after grassing the courses ended up too smooth and too perfect looking, and thus unnatural. I guess the golden agers didn't have this trouble because, even if they used machinery back then, it couldn't get rid of all the edges and contours and abruptness (as do today's machines), and so when the course was grassed and softened, you'd get what we think of as the naturalness of golden age design.
Peter