This refers to the SIGNAL ground for a balanced signal not an electrical EARTH ground. A balanced signal has a + (positive), - (negative) and shield ground. The Ground Lift interrupts the signal from the shield ground.Total FALSEHOOD. If that was the case there would never be a ground lift on pro audio electronics. Check your AXE.
100% agree with FractalAudio, not safe or advisable in any way, shape or form to remove, modify or alter the ground pin on any 3-prong electrical cable or cord.