A few years ago when I still had a mix of film and more digital cameras, I subscribed to a bunch of different popular photography magazines. There was a frequent ad in the back pages for a lightning trigger, which I figured out was triggering off the light of the lightning, and since most shutters (especially the electronic ones) were quite fast, what you got was part of the original strike and then any return strike since apparently the duration is way longer than that what a strobe would have. I do recall seeing and feeling that a strike was a bunch of repeat arcs, and this would make sense. I don't know if there are any that use a trigger built on the RF that a strike generates or not. I cannot recall the name of the unit, but like so many things that are cool, they may have saturated the market after a couple years.
I'll try to find something about it, especially since it used technology and the physics of a strike to grab the shot.