David,
Perhaps I can help clear up your frustration.
Yes, the proposed development put together by Olmsted and Vaux for the Real Estate company “adjoined” NGLA, but only in the strictest sense of touching a single point along a boundary. However, the vast majority of the land adjoining NGLA was not part of that Real Estate plan.
How little of that proposed development actually touched the course can best be seen in this aerial from Brad Klein’s terrific book, “Building Sebonack”. Here, one can see out across the entire NGLA course, and virtually all of the land bordering the course (on the right in this picture where land for Sebonack Golf Course had been cleared) was available for the Real Estate company to sub-divide for building lots but they chose not to. In the far distance near today’s 9th green and beyond was the planned development as well as the Shinnecock Inn.
Macdonald told us that everyone thought the land was more or less “worthless”. It was worthless for farming, and apparently it was so overgrown and bug-infested that it was considered worthless for housing development, possibly because of the anticipated cost to clear it.
Whatever price the Real Estate company wanted to charge Macdonald for his 2.5 acre addition (at least $1,000 an acre they said, and told him they’d gotten offers for more), it sounds like a negotiating ploy. It wasn’t until 1917 that they finally got a buyer (Charles H. Sabin) for the 300 odd acres next door (today's Sebonack GC) that had never been surveyed for housing. I’ve yet to find a purchase price for that transaction but maybe you can because I’ve got a flight to catch this afternoon.
As for the overall question of the golf course adding value to the surrounding Real Estate development, unfortunately that never happened, at least not quickly enough t help the Real Estate company.
As related in Goddard’s book over 90% of the planned lots never sold.
”A comparison of the Olmsted and Vaux survey map of 1906 with a similar map put ut for auction purposes in 1925 is instructive in this respect…It shows virtually no land sales. The eighty blocks covering thirteen hundred acres in the middle of the Hills were almost completely or more than 90 percent unsold.”As far as appreciating land values as a direct result of the golf course, that didn’t happen either, or at least some speculation in the 1920s that drove prices higher didn’t survive long-term. The book later reports,
”The Hills thereafter languished through the 1930s and 1940s and prices fell back to almost nineteenth-century levels.”Hope that helps.