Paul,
You asked, "Tom...do we have any evidence that models were created to study beforehand and used as a construction aid?....most designers create 3D models of ideas in the dirt as a communication aid but it seems to me that trying to work from a preconceived model would be cumbersome at best... Or were they just after the fact tokens of interest?"
Tilly used plasticine models as a means of defining his vision for both hole & green as an aid before construction. A fine example of this can be found in his letters to 5 Farms.
In his ciontract documents for the project he wrote, "In addition to the detailed plan of the courses, I agree to provide working models or cross-section drawings, with elevations, for the construction of the Greens, for the 18 holes first to be constructed; and afterwards for the second 18 holes..."
Note, the models were for THE CONSTRUCTION of BOTH holes & GREENS & prior to construction
One of the drawbacks of this method can be seen in the telegram that he sent the club that one of his visits would be postponed "until next week. Arrive Tuesday morning… badly sprained wrist will prevent my manipulating Plasticene for models until that time…"
That these models provided the needed information is also seen from another letter where, in discussing the project, he wrote, "I find that he [Robert Scott] has followed my directions faithfully and well…”
Tom Paul, regarding the models for NGLA, there was a series of articles written as it was being built published in Golf Illustrated month-by-month. These showed the individual holes of the new course by pictures of the models.
I will look it up & give you the references...