Garland,
Not sure why this topic rankles your feathers this much, but Broadie does show a descending line chart, noting that any pro above the line is more accurate than average, below is less accurate. It's not that he doesn't acknowledge there are exceptions, but for golfers, he (and others who use stats similarly) thinks using stats to play for avoiding the miss is a statistically smart move. You have given some one off examples, which don't really matter, other than proving that there are exceptions to every rule. I believe his statistics are still valid for design use.
The data I mostly use isn't from his book, but from his 2009 golf metrics paper, which is obviously a foundation for his book, although I note a few differences I can't reconcile but haven't called him to discuss. For me, even though his data was then just 513 A players and 513 D players, from which I have extrapolated the B and C dispersion patterns. Surprisingly, those 513 shots are the most data available anywhere on amateur players, although the USGA/RA has been doing similar work in their last three distance reports, and before the Broadie data above, it did a one day, 150 shot dispersion study on a course in NJ. BTW, those two studies and a few others I have collected from gca's over the years, seem remarkably consistent to me, although I am no statistician.
I feel pretty comfortable in using that to determine that if I want 1 in 8 D players to stay on the short grass to speed play, my play corridor needs to be X feet wide, and usually about 125%-150% wider on the right than left. Of course, as I note in my book, accomodating 1 in 8 D players probably requires an area the size of Montana, LOL. My perception is that having at least some data that can corroborate that I, a) thought about it, and b) am statistically above the vague "preponderance of shots should be contained" legal theory is my driving force in using his and other data.
Which brings me back to the question of why this data, or disproving it, seems so important to you? Just asking.