I understand that...and appreciate the explanation, but when a perp is in your face and your life is on the line, your body's chemistry will start to change...immediately...and it affects everything you do/see/hear. So yes, practicing it is the best way to prepare you for it, but truly, nothing ever really prepares you for the actual thing. You're just practicing what you think will happen and doing the best you can to prepare for it. The training will help, don't get me wrong, but the way you think and react during the real thing will be VERY different than your class. My .02