In 94 I was the pointman clearing the Haitian Police Compound and Commandants house. I learned 2 very important things from that event.

1. Rifles suck in tight spaces.
2. I need to find a way to mount a light to the weapon.

That was back before lights became tactical, and any weapons had rails, to my knowledge. Heck, that was before Tactical existed. We still used crook neck flashlights. I think they were about 3 lumen. Junk. Try opening doors, and moving obstacles with both hands full. You will sacrifice something. It is also very un-nerving as you try to determine if that is a bad guy hunched down or just a coat draped over a chair when you don't have a light.