I'm in agreement with those who say the overdevelopment of "hard skills" is the only way to spend your time. It's actually the only shortcut to "mindset" bullshit, because it at least builds confidence. Folks either have the capacity within them to develop emotional control, or they don't. Some (very few) are ice cold from the jump, but most people develop that with experience and repeated exposure to stressful situations that require them to perform at some level (the 'veteran' effect). The ONLY effective way to a shortcut is developing marksmanship and weapon manipulation at speed, so you KNOW what you can do in a given context. At least have confidence in your skills.
The difficult part of this is that to develop really good skill in this area takes work, especially away from the live range. Dry fire is THE way to do this, but not only are cops lazy and busy, most departments ACTIVELY discourage this type of training, because of the risk of accidents. So you are in effect limited to whatever minimal time they have on the live range to improve their performance. Like @
HCM said....one end of the curve will listen, buy Stoegers Dryfire book, watch him and Pranka on Instagram and listen to their discussions, take classes, etc. But the reality is that most just want to 'qualify' and get out.