Well, he does this so you don't have to.
Not exactly.
Anyone that's done a amount of battery connects and disconnects will have had an oops moment and suffered a burn or damaged a tool. Those innocent looking batteries pack a healthy punch especially when series'ed or paralleled up as in heavy equipment and more commonly these days in solar installations.
I knew a mechanic that suffered a bad burn on the wrist when he dived under a car bonnet while still wearing a watch with a metal strap.
Be careful out there.