David,
Honestly, I think by jumping in and out of this conversation you are missing important points.
Please go back and re-read the Macdonald letter and then let me know what you think they were being asked. They even referenced the fact that they couldn't tell if it was either enough land or whether a first class golf course on it without even a topographical map. So, they were going by gut feel of the general dimensions of the property, and suggested that logical next steps before going out and buying the property were to get soil samples and send them for analysis.
Any other reading of this letter is pure supposition and wishful thinking and trying to put things in there that it clearly does not contain.
In fact, if Lloyd and the Site Committee, who were the ones charged with finding a site, had really asked M&W to do more at that time as you suggest, then this letter would really be a pretty polite brushoff, don't you think?
On July 2, 1910, after over three years of construction NGLA was just finally just coming into playability.
From "The Evangelist of Golf";
"On July 2 1910, 14 months before the official opening, the courses was finally ready for a test run. An informal invitational tournament was held for a select group of fouders and friends invited to participate."
"It was noted the tournament served the purpose of revealing any design shortcoming that needed correcting."
As seen above, the course didn't have it's official opening until 1911. David has challenged this and I'm not sure what evidence he has that contradicts George Bahto's book that outlines these timelines.
In any case, I think M&W had their hands and plates quite full at the time that they were being asked to determine the suitability of the property (remember that the records state that Merion was still looking a a number of properties at the time) for golf for Merion in June/July 1910. For them to come out for a day at Rodman Griscom's invitation was quite nice of them, actually.
This timeline also shows that not only was Macdonald not viewed universally as a great architect by this time, but that many of his friends and best players had not even seen the course at NGLA prior to then. They knew he had been studying, and working on it, but many had no idea of how great it was at that point.
The letter was to H.G. Lloyd, and not Hugh Wilson, probably because Lloyd was the head of the Site Committee, which Wilson was not on. That would have been appropriate protocol.
Peter,
Your assessment is very accurate, I believe.