And negligence on the lineman for not making sure service was disconnected to the circuit before starting work.
This exemplifies your misunderstanding of the trade.
When working on "circuits" we physically disconnect the "load" side of the "circuit" from the "line" side of the circuit.
All of the the conductors on the "load" side of the "circuit" are then tested to ensure that they are de-energized.
The circuit is then "locked out and tagged out".
The "load" side of the circuit" is now safe to be worked on.
The problem occurs when a generator that is connected to the "load" side of the circuit. This is what is called "backfeeding." It is called that because the generator is supplying power in the reverse direction.
There is no way possible to locate one of these generators until it energizes the "load" side of the "circuit." And at that point, death or serious injury are the indicators that someone is negligently operating a stand-by generator.