All that said, my usual carry piece is a Colt Detective Special with +P rounds. I carry a speedloader for those heavy days.
I can see what happened here as feasable, even with a revolver, if the gun was holstered carelessly with the jacket pull in the trigger guard. And if you holster and unholster your gun daily, the force of habit can eventually allow you to become complacent, and less cognizant of safety.
I carry everyday. I am never complacent about my weapon. I have left my home in the morning without my cell phone and my lunch, never without my weapon.
I forget things and leave them in my vehicle. Never my weapon.
I am not disagreeing with you. I think it is a matter of training.