Peter,
In the "Redan" article that he and Whigham wrote for Golf Illustrated he said:
"TAKE a narrow tableland, tilt it a little from
right to left, dig a deep bunker on the front
side, approach it diagonally, and you have
the Redan. At North Berwick, of course, all these
things were done in the beginning by nature. The
only original thing that the greenkeeper did was to
place the tee so that the shot had to be played corner
-wise, so to speak, instead of directly down the tableland."
So, I presume that the architectual "principle" in the topographical layout that he saw was as described above.
He then went on to write:
"And when you come to think of it that is the
secret of most of the great holes all over the world.
They all have some kind of a twist.
Said the North Berwick caddie to Mr. Macdonald
when he was on the quest for ideal holes for the coming
National Links “Here’s the hole that makes a
man think.”
So, another "principle" that he may have had in mind already is that great holes have a "twist". But the caddie may have implanted another "principle" - that a great hole "makes a man think".
They go on to write about the options for playing the hole in different ways and different conditions, and the difficulties in doing so. So, perhaps he saw some of the inherent difficulties.
The article also notes that the slope of the green site was natural at NB and was natural at his NGLA replica. But he does allow that the architect could create the landform. So, perhaps the natural landform inspired him but he wasn't averse to recreating it.
So, perhaps the answers to your questions is yes, yes, and yes. But that's pure speculation.