Originally Posted by PaulRivers

Seems like you're talking past the point. Lightning goes wherever there's the least resistance. If your metal frame is a little less resistant than a nearby tree, the lighting will go through the metal frame. If your frame is a little more resistant than a nearby tree, it will go through the tree. If you're on the top of a hill and in an area of less resistance in the air, well, you're screwed either way.

I think a little bit of it is tongue-in-cheek against the "carbon will assplode if you touch it" crowd though. With the absurd claims of carbon fiber being fragile made by the anti-anything-new crowd, it's kind of amusing to tell them an almost-as-absurd story about how you ride carbon because you want to be protected from lightning.

I suspect a metal frame material might make a very tiny, small increase in your odds of being hit by lighting, but it's very very small.