Niall,
I am a bit confused. You appear to be making contradictory statements. Can you clarify what you mean when you say, "rather than appearing different to hole depictions of the time, they look remarkably similar to the type of basic plans routinely seen in contemporary newspapers..."
with this earlier one, "Secondly, the Road Hole sketch defines the fairway. Off the top of my head I'm not sure I've seen this before on sketches of this type."
In addition David agreed with this second statement of yours. In reference to the fairway lines and precisely shaped representations of tee boxes he wrote, "I don't remember the details of every drawing I've ever seen, but I feel safe in saying that, generally,such details on drawings from the turn of the century were unusual, if they existed at all."
That is why I stated, "That they should appear different from hole design drawings of the day shouldn't surprise one but rather should be expected. They reflect what he saw and what he wanted to remember and think about."
Niall, Joe & the Lurker, these were not for artistic purposes. Tilly was studying the courses and specific holes in the U.K. for the specific purpose of understanding the concepts that define great course architecture and design. These drawings, as well as many others that he did constantly throughout his life show this. Remember too that he spent a great deal of time talking to others on these trips about golf architecture and design.
In addition, he also brought along his 5x5 camera and photographed everything from courses to players to St. Andrews itself. Many of these photographs can be seen in the pages of GOLF & other magazines beginning in 1901 and onward. He used the photographs of the holes and features (there is a wonderful one of the "whins" at St. Andrews as an example) in his studies.
As for why he delineated the fairway there are a number of possible answers:
1- That's what he saw on the hole.
2- He was defining not the fairway/rough line but the areas of "Hilly Ground" which is what he wrote on the drawing and not rough. This possibility is what I believe because when you compare the Redan drawing you'll see that he defined the areas of "Rough" on the hole.
3- Any of a multitude of possible reasons that one might come up with.
We'll probably never know the definitive answer.