Just a few notes here...I spent 4 months under the tutelage of
Jim Lindell. He was an employee of the Kansas City Police Department at that time. He didn't teach live fire at all. The 'retention' he taught was how to defeat gun grabs from the uniform holster- and he taught it very well.
He also taught defensive tactics and physical training- and he taught them exceptionally well. Lindell's systems were derived from the better principles of several formal martial arts; balance, blinding speed and efficiency of motion to provide power to the block, strike, kick or takedown. The end product was an amazingly fast, simple, and natural library of full-force block/counterstrikes as conditioned responses to an attack from any angle. It is no exaggeration to state that these 'blocks' often stunned or hurt the recipient nearly as bad as the counter-strike.
Jim's approach to training methodology was anything but dogmatic, and an automatic transition to 'Plan B' was built into most of them. A a part of a recruit class, it was impossible to miss the effectiveness of his training methodology. I adopted it at every opportunity when I started teaching firearms, ten years later.
'Speed Rock', 'Yank & Blast', Emergency Action Drills (EAD),
Retention Firing or whatever you wish to call it should be taught as a fluid, adaptable 'counterstrike' to deadly threats at close range- which I consider 'inside 5 yards'. I like the term EAD myself because it leaves no doubt that an EMERGENCY is underway NOW and it is time to do nothing but shoot down your attacker. It is commenced one-handed with a transition to two-handed shooting if conditions require (body armor drill) or allow it.
At contact distance the gun is close to the body as the weak hand blocks contact weapons or palm-strikes at the face. The gun is held a few inches further out from the body now that semi-autos are the norm. If an attack moves in from 6-7 yards the handgun can still be deployed one-handed and fast, accurate fire is delivered and maintained- along with balance and the ability to move off the line of attack.
Frankly, I never noticed any 'problem' with teaching this skillset. No conscientious or credible trainer would teach stationary, 'retention' firing as a singular solution to close-range attacks. I have never missed an opportunity to attend or conduct police firearms training in the 28 years since I first stepped onto a firing line. In that time I have never seen it taught as such. Perhaps it is being taught incorrectly 'somewhere' but I learned long ago that since I'm not 'selling anything' my time was better spent worrying about what works and what doesn't. I can tell you with confidence that several officers I have had the pleasure of training have survived deadly attacks (both human and animal) that came from oblique angles, in near-total darkness and from 6 feet instead of six yards. Their account was that they reacted immediately as trained, without conscious thought, and that their fire went exactly where it did during EAD exercises- into the middle of the threat. All but one were moving 'off the line' when they realized that they had been in a shooting- and 'Won!'. I take no credit for their success. I taught them "A" way- not 'the only' way.
Those officers took the initiative to learn it well and they adapted it to the fight they were handed. The good came away unscathed and the 'bad' got stopped. 'Repeat offenders' seem to be missing from the equation. That's a positive training result in my book.