Diplomacy has never been my forte so I'd appreciate any advice on how to suggest changes to an experienced shooter's gun handling.
My situation:
An elderly relative recently decided to buy their first semi automatic pistol and asked me to accompany them to the range while they get accustomed to their new carry pistol. They were top shot at the academy (in 1970?) and have excellent marksmanship, but have never had to rack a slide or manipulate a safety, decocker, slide release, or mag release. I wasn't asked to train them (nor do I consider myself qualified to do so), but I have been suggesting various DA/SA & reloading drills to try and help achieve subconscious competence with all of the semi auto's functions - drills they struggle with but seem to appreciate in small doses.
The primary safety concern I have is that they tend to allow their index finger to wander inside the trigger guard when manipulating non firing functions. I suspect dupuytren's is partly to blame (fingers can't straighten - a common affliction among the elderly in my family), but even a curved finger can rest on the frame while racking the slide. Thankfully they have good muzzle discipline, but without intervention I fear it is only a matter of time before they have a Negligent Discharge...
I've casually mentioned a couple times "careful that your finger isn't near the trigger until you're ready to fire," but that definitely wasn't appreciated and hasn't been effective.
Does anyone have any suggestions? I'm sure real trainers must encounter this stuff all the time...