David,
I believe and have postulated that CBM's philosophy of what was required in terms of acreage changed dramatically during the creation of NGLA, and I believe it's because when all was said and done, his strategic holes required MUCH more in terms of overall hole width than what he originally conceived. I believe this all took place during the time he routed the course and started to look at strategic options, and how a weaker golfer might need to play his holes.
As I posted earlier, Macdonald originally believed and earlier wrote that fairways were becoming much too wide, and wrote that there was no reason for fairways to be larger than 45-60 yards in most cases, again as an average depending on the type of hole.
Here, he breaks out the "scoring" and important parameters of his "Ideal course".
It's very easy to see where his earlier idea that he'd only need roughly 110 acres for the golf course came from.
Assuming a course of roughly 6,000 yards long as "Ideal", and assuming that with 50 yard wide fairways you might need setbacks of another 25 yards on each side in an out-and-back routing (very conservatively totaling 100 yards of width for each hole with 75 yards between centerpoints of adjoining fairways ) and another 500 yards to walk from one green to the next tee (although ideally, CBM felt this should be a very short walk indeed), you come up with 134 acres.
So, it's no wonder that by 1910 when coming to Ardmore and looking at roughly 120 acres of land, his cautionary reply was that it was going to be a tight fit, but recommended a course around 6000 yards and he thought they could make it.
So, then, what was different at NGLA?
Well, as mentioned, CBM broke his own rules in terms of "do as I say, don't do as I do".
To create his desired strategic options, CBM created hugely wide fairways in most cases...my rough estimations of their widest points, clearly designed for maximizing strategic options using Google Earth are as follows;
1 - 60 yds
2 - 65
3 - 56
4 - 65
5 - 70
6 - 75
7 - 135
8 - 80
9 - 70
10 - 69
11 - 65
12 - 83
13 - 60
14 - 48
15 - 38 (Narrows)
16 - 86
17 - 90
18 - 82
I'm not sure at what point in his evolution that Macdonald realized he'd need much more land to build the type of holes he originally envisioned, but we know in 1906 that just before acquiring the Sebonac property he tried to buy 120 acres closer to Shinnecock, so it's unlkely he made that move without thinking he could build his ideal course there.
I think and believe the evidence shows he went into the NGLA project and Sebonac property exactly as he promised the Founders in his original agreement...needing some amount of land in the 110-130 acre range for the golf course, 5 acres needed for the clubhouse, and the remainder of his targeted 205 acres for building lots for the 60-70 Founders, which might be an acre-and-a-half as he originally wrote in 1904, or an acre as Whigham wrote in 1906, depending on the size of the course.
It's just that when they got done building the best course possible, they had used most of it up due to the increased need for width, and had to make some accommodations to the Founders for what was much less "Surplus Land" than originally projected.
His original 1904 agreement cited needing 205 acres, he secured exactly 205 acres, and the thing that changed by the time the course opened is that his golf course had grown from his original projection of 110 acres to something closer to 160-170.
It's pretty tough to divide the surplus land of 35 - 45 disjointed acres so Macdonald likely convinced the members to just accept some other compensation.
I'm also certain that his primary goal all along was to build the best golf course possible, and believe that his "giving something back" to the members in his original proposal was designed to get money to back his project, first and foremost.
I'm pretty sure he wasn't too disappointed with either the outcome or the lack of Founder's building lots.