Example, an electrician connects a temporary generator during a power outage using a cord with male end connected to a breaker that will be removed when generator is disconnected.
If the main breaker is lockedout (&tagged)
how is this less safe to the lineman than a transfer switch?
The problem is that someone backfeeding a generator into the house wiring may forget to turn off the main breaker. The transfer switch is designed to make sure the user disconnects the house wiring from the POCO and connect it to the generator. The transfer switch requires only one action, where the "backfeed the generator and shut off the main breaker" requires two separate actions. Which might not get done. It's a bit like the rules at the shooting range: "put the safety on, take the magazine out, keep the gun pointed to the floor, and never aim at anyone". Redundant, but with something that can be lethal, you need redundancy.
