I wouldn't agree with all of that. This goes back to the difference between "shooting" and applying shooting to "problem solving" as a piece of a much bigger pie. One of the biggest reasons we had a lot of success with a "Weaver like fighting stance" is the due to the use of a flashlight in combination with a pistol to search and engage with. I spent a lot of years with Mike Harries. When you work a lot with a handheld light, you tend to use a technique that works well with it. Here is reality-the ISO based flashlight techniques totally suck-period. It wasn't till the advent of some of the X series Surefire WML's that you could actually work somewhat competently with a light and a ISO platform. This is still not a replacement in L/E circles for use of a light, BUT a WML will work well for Military units with lesser restrictive ROE's, and for most civilians who are working off reactive response for ID only and not really doing a lot of searching and other tasks with their lights.
I would agree with the assessment of the stance itself. We used a "Weaverish" hand and arm configuration out of an F.I. stance as the basis for what we were doing. Again, a little less effective "shooting", but more effective for everything else that was often leading up to and post shooting.
The key to early Gunsite was not purely Jeff Cooper, but the folks Cooper attracted to the laboratory. Mudgett, Helms, Reitz and later others from LAPD. Guys like Bill Jeans, Clint Smith, Pat Rogers, Mike Harries, the Stock brothers, Ken Hackathorn, Bill Murphy, Louis Awerbuck, and many others. A lot of "thinkers" were there who took what was going on very seriously, and were able to apply these techniques and tweak them. While I never got to meet Cooper, I have read almost everything he has ever wrote and have a HUGE respect for the man. With that said, many found that Jeff's ideas would not work in many urban settings without some tweaking. Most tended to be more pliable than Mr. Cooper. What was apparent is that most of the folks from that world did not fall into untested ideas. They tend to stick with what they have found works in the field. They were open to what came from the competition world, BUT were very wary of application in the field. I am very much wired the same way.