[Professional Engineer]

does anyone here know the number of amps (current) that flowed through this poor unfortunate chap.

Once the breakdown resistance, of skin, was exceeded, probably a few hundred. BTW, it takes about 50milliamps through the chest to kill a person.

[spinestein]

I got about a 30,000 volt jolt while twisting the distributer on my car that had high performance coil on it and survived quite nicely, although the shock is very un-fun. The current is low enough that it's relatively harmless, but I did have fun conning my friend into "helping" me tune my car after I discovered this trick.

"Come here and grab a hold of this while I start the car."

He jumped halfway across the garage.