When I was in LE, some times I had to clear parts of a building alone. Opening doors and clearing the room.
A flashlight in hand means you have two hands full and a knob needing turning. My solution (as I couldnt afford a ULT for my HK) was to place the light in my gun hand, and hold both light and gun... this would let me fire the gun if necesesary, while panning the light.
Any other tactical solutions that could work here?