Peter,
Interesting topics. In theory, gca ought to be better as time goes on. Only problem is, the canvass changes, from real estate to environmental considerations, etc.
There is still variance of opinion. First that comes to mind is visibility over blind shots and maybe "definition" which had become standardized concepts. And naturally, a few architects, seeking fame and fortune by being different, came along and told us "not so fast." For some reviewers a new course without those elements has some mistakes, for others, the old style is the mistake and the new style has all the answers. Neither is totally true, of course.
And, that doesn't even begin to address site specific design applications, or Owner's instructions/goals which are infinite.
Was looking through some old articles last night and saw a critique of a then new course measuring well over 7K set within a seniors community, where most would play under 6K. Sometimes, entire paradigms, like the CCFAD everywhere, are mistakes, or at least bad fads. So, we saw the inherent problems with courses like that, but seemed to think other factors (bunkers for visuals, selling real estate, winning awards, etc.) over rode some well known basic considerations, like making it a course you could play every day.
Mistake? Giving the Owner what he wants (even if mistake) or keeping up with the times, knowing full well times will change again?
Sorry for the long non-answer.