It sounds to me that this was a short budget build.
The WPA must have been pinching it's pennies after spending a million dollars at George Wright (1931-38). I like the reference to not obstruct the vision of the greens.
The course is a very good example of Ross on flat groud. I would not be surprised that the drainage ditches were meant to be both drainage and a hazard.
With the elevation change of practically nothing it was difficult to drain a property like Brunswick. The drainage ditches are reminiscent to those at Timuquana although most of the Timuquana system is hidden on the outer perimeter in the trees.
Neat place, Brunswick. Can't wait to see it.
Thanks for your research.
MJFay