That would require a dedicated equipment grounding conductor to EVERY device (switch and receptacle) and piece of utilization equipment (light fixtures, hvac, etc) on the job. So a 277v. circuit with 30 fixtures and 12 switches would require 42 grounding conductors. Thats 42 grounds, 1 hot & 1 neutral just for one circuit. Impossible in my opinion. He MUST be speaking of the G.E.C. and not the equipment ground. A simple typing mistake or mis-understanding of proper terminology. If not, he's an idiot.