My stupid human trick:
For a while I worked in a PV system training center. In the facility we had a mockup of a standing seam roof where we built arrays on S-5 clamps, and overhead we had several big mercury vapor stadium lights that could put enough light flux on the modules to commission the systems we built.
One day I was troubleshooting a string of modules that was showing zero volts (later I discovered it was due to a badly made up connector in one of the home run conductors), and in the process I had disconnected the positive home run from the DC combiner. Unbeknownst to me, when I jostled the wire I caused the faulty connector on the other end to make contact with the wire. When I went to reconnect the wire I noticed that the strands had gotten splayed by the terminal screw, so thinking that the wire was not energized I grabbed the strands with my fingers to squeeze them back together so I could fit the wire back into the terminal. I was in shorts kneeling on the grounded metal roof and the string Voc was something like 400V.
Two things saved my life. One was that the array was indoors and the only light falling on it at the time was from some fluorescent tubes up on the 20' ceiling. The other was that it was a mockup on the floor and I only fell about three feet when I fell off the roof. If it had been a real roof in sunlight I would not be here to write this.