I am not going to debate the pros and cons of weapon mounted light versus non weapon mounted light the OP is interested only in how to use a weapon mounted light.
That being said I have given this some thought and if defending a perimeter from behind a berm or in a bunker or foxhole, I would prefer two persons, one the shooter with a flash suppressor and low flash ammo some distance from the other person who runs the light attached to a piece of PVC plastic pipe so he can stay down in the safety of behind the berm or in the bunker or foxhole, the shooter would do the looking directing the man controlling the light by voice commands or cell phone or radio contact, on up or down or right or left, and stop when on target. A periscope would be interesting to use also if you did not have night vision or thermal.
At one time for room clearing, i thought of inventing a light that was round and threw light in all directions that you could throw in a room check for threats and if no threats retrieve the light for the next room. While that would be not as good as a flash bang grenade, I read some where that Israel who are always creative, invented the same thing combined with cameras and a grenade, throw the light into a room, if the camera(s) expose a threat, detonate the grenade.
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