Ed,
That's an interesting topic.
Could the answer lie in the "negative" mind set of most golfers ?
I too have played some of my best rounds on a first time play.
One reason I believe is that I ask my caddy to ONLY inform me of where to play, and NOT to inform me of where NOT to play.
Thus, my feed back from the caddy is all positive reinforcement.
Repeat play reveals more of the negatives, the mental magnets that attract us to adversity if not disaster.
There may be a parabolic curve to this, where eventually, one comes to terms with the architecture, understands it and knows how to cope with it.
It's a very interesting dynamic.