I have witnssed a fire caused by a shorted switch harness that would not have happened if there had been a diode in the system.
So I will continue to fit diodes in the hope that I never need them.
It seems like you want your diode to act like a fuses?. If you use the correct (A) diode it will become a piece of wire if overload. Example like a car radio or CB radio when the polarity reverse
