I don't see a >600 rule. I guess the worms just jump a little higher if you have a fault.
Actually the fire shooting out of that hole might take birds out of the sky
I have seen MV conductors down and dancing up off the ground. It is a sight to see if you have a safe place to watch from. (In my case a roof top bar in the Keys watching them clear out a parking lot). It went on for about 45 minutes before the PoCo showed up to pull the disconnect link.