Our bodies differ greatly from one officer to the next. We vary physiologically and biologically, and our skills and abilities range from acceptable to superior. That being said, there is no "one size fits all" flashlight or flashlight technique. Therefore, we have to provide a training opportunity for our officers to experiment with what works best for them. Which light can they deploy quickly and work in harmony with their weapon? Which one will either fit in their pocket or on the remaining space on their duty belt? The light will not do you any good sitting on the seat of your patrol car, or in the pocket of your jacket hanging in the back seat. If you are on duty, that light must be with you!
Some other quick thoughts about low light: most would consider low light to be our enemy, but if you master the flashlight it becomes an ally. Darkness allows us to move without detection, and we control our adversary's ability to see us and anything else. The brilliant, strobing, unpredictable light becomes a "force option," causing confusion and fear in our subject. Movement combined with blinding light gives you a superior position, one which demoralizes and causes extreme consternation in what would normally have been an opponent with an advantage.
Remember also that light without movement can equal death. Think of being on the opposite side of the light. Your first inclination, indeed your only option, is to fire at the light. If that light is steady and with no movement, that shot is a "K5" shot. Always think in reverse images, what I see of the bad guy, the bad guy sees of me.
A final thought...any piece of equipment can fail. I don't care if you paid $150.00 or $50.00 for that light, there is a possibility that it will stop working when you need it most. The solution is to carry two. Flashlights are so compact today that carrying two is no burden whatsoever. There is an old theory which states, "Two is one and one is none." That adage applies here as well. Low light training puts us ahead of the power curve if conducted properly and regularly. Get on it, my friends!