Edited to add: Have you ever heard of a timing light for an engine? This works exactly the way you are describing.
The timing light is then pointed at the flywheel on an engine, which has numbers or marks stamped into it. Each time the spark plug fires the timing light (which is hooked into that same current via induction) lights up for a brief amount of time to show at what timing offset the engine is currently at. (this all happens at hundreds of rpms a minute).
so I'm not sure it's the same
Never underestimate the ability of machinery to rapidly render you dead.
Never underestimate the ability of otherwise intelligent people to intentionally disable safeguards, or guninely make mistakes.
So far, the discussion sounds like it's a theoretical possibility. If it's a real possibility, then it's something that should have happened a number of times.