I have a basic theory and understanding of the mechanics of a firearm, but a firearm is a relatively simple mechanical device. A radar, a lidar, and even a breathalyzer, are far more complex and the courts do not mandate that the officers have anything more than a functional understanding of their operation. NO court I am aware of mandates that I have to explain how a firearm works in order to utilize it. I have a working understanding of these devices sufficient to safely and effectively utilize them, but, I cannot speak in depth concerning the science behind them.
my "real job" required me to use them, not to disassemble them and/or conduct a seminar on their operation.