so, both my kids attend the MMA school - both are at brown belts level - they had there somewhat a similar thing shown/taught by their sensei as a part of self-defence practices. specifically it was a training on grabbing the arm with gun pressing into your chest, and grabbing the draw.
my oldest kid is 15, we then talked about it and at home i showed him how his martial arts tech he was shown would unfold in a real life scenario with me having my gun in my OWB holster and him trying to get it from me.
so i a had to imprint it into his brain - if you will ever see a f#ck with a hand moving toward a gun - you dodge, run and hide. you do not attempt to grab that gun, ever.
you would think it is all stupid and absurd, but, it is actually a rather real topic.