In my case, I would be glad to renovate my courses. I doubt I am alone among either modern or historic architects in saying I would love to remodel some aspect of virtually every course I've done.
That opinion goes through some predictable time changes, too. I usually love a course when it first opens....A few years later, I've ;moved on to other ideas and concepts, and all of a sudden, a course is not among my favorites. AFter about ten years time, I can play my own courses, and remember what I was trying to do with an open mind. Then, a lot of the ideas become "cool" again in my mind.....if nowhere else!
Also, if a client called, it shows a lot of respect. Some go get another architect, simply figuring the first one just didn't have much talent. Then, they end up with a mish mash of ideas, and the whole course gets to be a mess, when in reality, the original architect would almost always feel like they did a good job, had some constrictions, or just didn't get everything just as they wanted.
Also, I think most architects realize that sometimes, even a design just fails in spots, or changes over time, ie, needs to have bunkers moved out, or greens flattened. Sometimes, a course goes from private to public, or vice versa, and the new "constituency" needs some changes as a result, but those changes don't necessarily imply the original design was bad.
So, I would probably approach the renovations with an eye to the here and now problems. As I occaisionlly like some quirk in my design, and there is often pressure to make this green "conform" to the style of the others, I would probably fight for the features that I liked, especially the unique ones not found elsewhere.....So what if someone doubled the hole?
In the end, its just a round of golf, no? And in the end, its just a golf course - a collection of 18 holes that someone, namely the architect - at one point in time thought was a good idea.
How many times have you heard the saying "It must have seemed like a good idea at the time?" I'm not sure, but I think that saying originated with my designs.....