Sean, I apologize for my virtual laughing. The comment struck me because IMO it is hard to underestimate CBM's influence over golf course design in America. Nonetheless it was rude and I apologize.
As for your question, I come at this issue from a historical perspective and have learned quite a bit about what golf course architecture in America was like before CBM and NGLA. If anyone has trouble seeing CBM's influence on golf courses, it is perhaps because his influence was so profound that it virtually wiped the map clean of much of what had gone on before. There are perhaps a few exceptions, of course, but not many. His ideas, principles, and methodologies were emulated from coast to coast, on existing courses and on new courses.
Simple things we take for granted in classic courses - like the importance of width and angles, like the importance of a variety of types holes and greens, like a variety of hole distances, like the availability of alternate routes for lesser players, like strategic placement of hazards, etc., like varying directions, like the importance of the soil and of proper undulations - were ideas propounded by CBM. Of course he did not invent these ideas - he was admittedly borrowing them from the links courses - but he is the one who popularized them in America, and perhaps he might have even had a hand in popularizing them elsewhere.
You mention MacKenzie and Augusta National, so let's take a look at what MacKenzie had to say about CBM regarding Augusta, and elsewhere. While St. Andrews gets mentioned a lot in conjunction with ANGC, the course was actually an attempt at an "ideal golf course" based on the best features from the great golf courses of the of the World. Sound familiar? Even at ANGC, one could argue that MacKenzie is following in the footsteps of CBM. It was his "National." Augusta National. And MacKenzie specifically acknowledged, that the work and writings of CBM and others had paved the way for the acceptance of a course like Augusta National:
. . . [W]hen I asked [Bob Jones’] opinion about the design of Augusta National, he said that the course would differ so markedly from others, that many of the members at first would have unpleasant things to say about the architects. A few years ago I would have agreed with Bob, but today, owing to his own teaching, the work and writings of C.B Macdonald, Max Behr, Robert Hunter, and others, Americans appreciate real strategic golf to a greater extent than even in Scotland, the home of Golf.
Mackenzie also wrote that CBM helped launched MacKenzie's golf architecture career when he and Darwin awarded CBM's design for "ideal two shot hole" in their Country Life contest, and then CBM built the hole at his Lido course.
MacKenzie thought NGLA a "masterpiece" and a "shining example" which lead to the excellence of many other courses. (He also noted his preference for NGLA over even Pine Valley:
North America is rapidly becoming a greater golf center than even the home of golf, Scotland. The average American golf course is vastly superior to the average Scottish golf course, but I still think the best courses in Scotland, such as the Old Course at St. Andrews, are superior to any in the World. In the East, the National and Pine Valley are outstanding, and the excellence of many other courses may be traced to their shining example. My personal preference is for the National. Although not so spectacular as Pine Valley, it has a greater resemblance to real links land than any course in the East.
It is also essentially a strategic course; every hole sets a problem. At the National there are excellent copies of classic holes, but I think the holes, like the 14th and 17th, which C. B. Macdonald has evolved, so to speak, out of his own head, are superior to any of them.
MacKenzie was quite clear about the force behind the excellence of golden age golf architecture in America, and the difficulty of CBM's task:
In the United States, golf courses are becoming more and more perfect. American golfers owe a debt of gratitude to Charles Blair Macdonald, who was not only the first United States Amateur Champion but the father of golf architecture in America.
He had an uphill fight in educating American golfers to an appreciation of a really good golf courses. On the National Golf Links, Lido, and other links he made copies of famous holes of the old British Championship courses, which was an expensive way of constructing golf courses, but probably the only means of combating criticism and familiarizing players with real golf. One learns by bitter experience how difficult it is to escape hostile criticisms when one makes a hole of the adventurous type.
. . .
A first class golf hole must have subtleties and stragetic problems which are difficult to understand, and are therefore extremely likely to to be condemned at first site by even the best players. One can only escape hosticle criticism by point out that a hole is a copy of such and such a hole like "the Road," "Eden," "Redan" or some other equally famous.
It was in this way that Macdonald was able to familiarize American players with real golf and make the work easy for other architects that followed him.
And . . .
The trouble in those early days was that all golfers except a very small handful of pioneers belonged to the penal school. Today we have no such battles to fight. I hardly come across a thinking member of a committee who does not belong to the strategic school.
Owing to the example and writings of C. B. Macdonald, Max Behr, Robert Hunter, and other able American golf course architects, the United States are absorbing the real sporting spirit of golf so rapidly that today, with the exception of St. Andrews and a few similar clubs, American committees have sounder views than have committees in the "Home of Golf."
So I think it fair to say that MacKenzie thought that CBM had a profound influence on golf course architecture in America. What do you think?
Who is next? Perry Maxwell? His CBM connection demonstrates just how widespread CBM's influence over golf course architecture had become, even by 1910 . . .