Did anybody in the war actually remove the tracers from the belts of his bomber's defensive guns?
I can find no reference to removing tracers from the belts of defensive guns on bombers.
A defensive gunner would probably want the attacking fighter to know that lead is coming thier way to make him think twice about getting close.
At least one Lanc tail gunner that I read comments by didn't think the guns had any real chance of downing an enemy fighter, but the tracers would scare them off.