Isn't your body the best path to ground when the outlet isn't grounded? I kind of see what he's up to, though. Basically, if you touch the hot wire, or one of

Isn't your body the best path to ground when the outlet isn't grounded? I kind of see what he's up to, though. Basically, if you touch the hot wire, or one of the screws that it's attached to, you probably get shocked. That is unavoidable; turn off the power before starting work to minimize your risk. (The risk is, of course, never zero, so do be careful even if you're sure the power is off.) If you connect neutral first and then hot, you still get shocked if you touch the hot wire... but you also short out if the hot wire that you're screwing to the terminal touches the neutral (or ground) wire. That will cause the circuit breaker to open (or failing that, a fire), defeating the purpose of working on an energized system. So I guess this procedure is optimized for uptime, at an increased risk of death.