What thE_29 said.
Legendary Short Circuit has a passive that triggers its damage on crit. This damage is electrical and non lethal. If you have Skippy and you are trying to get 50 kills to force it to switch modes, Legendary Short Circuit will prevent this from happening (because Short Circuit is dealing the incapacitating blow, not your bullets).
If you have quickhack perks, Short Circuit procs can do an astonishing amount of damage - in some cases, significantly more than the gun you are shooting or the melee weapon you are swinging. It adds roughly 40k non lethal damage to my katana strikes for example. It also applies to fists and this is how I was able to beat all the boxing missions with 3 Body and no stamina/melee damage perks in Street Brawling.