I recently saw MacK's construction drawings for the 1st green. He wanted some wild contours around and in the green, including a little false front. Looking at Byrdy's picture of the green in 1934, most of that crazy contouring seems to have been built.
As Dunlop notes, given those contours, an approach from the left (the bail-out area) would have to deal with a green partially hidden by the fore bunker and a nasty mound left front of the green. Approaching from the right was clearly the way to come into the green.
An elegantly simple strategic hole. (Well, given the contouring, maybe not all that simple.)
By 1940, the green contours look like they have been toned down quite substantially. It also looks like the green has been elevated slightly.
These are just pictures and pictures can sometimes mislead, but something seems to have happened to the 1st green between '34 and '40.
Note that the fore bunker became a greenside bunker (moved about 30 yards) by '48, which must have been RTJ's doing.
Bob