Yeah, the AMU armorer's feel the same way - slide-to-frame fit is the variable that LEAST affects accuracy.
I spent the weekend re-auditing the Black Badge course, mandatory after an absence of a couple of years. My wife will be on a later course as she wants to add another shooting sport to her life. I went into CAS as an IPSC burnout and it didn't take long for the IPSC mentality to follow with Cowboy 'race guns', short stroke lever actions, etc. C'est la vie .....
But, the major difference was in general gun handling skills. Although some of the rules can be anal, the BB course is arguably the best safe gun handling course out there available to anyone. Most of the CAS folks I know could benefit from it. And so could the police!
I have no idea why there isn't a CAS equivalent. Our club has a mandatory "holster qualification" course that just stresses a safe draw, reholstering, muzzle direction while on the move, etc. ALL people wearing a gun on the range must have this. We've had too many incidents of improper and downright dangerous gun handling, often from police recreational shooting. What they do on official training when they rent the range is up to them.
The guns I saw on the Black Badge course ranged from the top end, optically sighted, compensated 'race guns' down to my stock Remington R1. I also had my tricked out Series '70 Gold Cup, but I was trying to make a point. My long years of experience in IPSC more than made up for it's lack of sophistication and I was the only 'student' not to incur penalties for misses or hits on 'no shoots'.
The gun didn't malfunction once.
This could not be said of the 'big boys' who incurred a few while showing us how it's done with high end guns and gear. Among the students, the guns that gibbled were a Ruger SR1911, a Norc, a Ruger P-95 and a couple of European 9mms. Some of these were 'shooter induced' malfunctions, others related to ammo. Chalk it up to lack of experience.
I wore my Davis holster the first day for the pure nostalgia of it, the only leather rig there. This could be worn 'concealed' and I often did when that was a requirement in IPSC. The second day, I used a new Blade-Tech, which while looking oh, so kool, was no faster on the draw and looks downright silly, the gun butt jutting out making it vulnerable to hitting door jambs, furniture, etc.
I wore both around the house for a week before the course, and there is no doubt as to which holster is truly 'practical'. I forgot I was wearing the Davis, but was always conscious of wearing the Blade-Tech.
Now, I have to work on getting the IPSC guys to cross over and try 'Wild Bunch'. The head honcho is interested as he realizes that some cross over will benefit both disciplines and increase participation.