SD et all,
Physics was never my favorite subject, but it seems logical to me that for a disspator to work properly, the boat would need to be grounded. I put a large one on my last boat and lived in Fort Myers, where there are very severe lightning storms every day. I was never struck, other boats around me were. My mast was the tallest. Did the dissipator save me??? Only God knows that.
Not to dig up an old thread about grounding versus not grounding, but if you ground your boat and do not think you are seriously increasing your chances of getting struck, I think you are kidding yourself. However, if you don't... better be prepared for the consequences if you do get bit.
I have heard the static popping on the mast. Eerie. A disspator is not going to save, just reduce the odds that you get hit and instead smack your neighbor (and maybe curve back around and hit you). I guess my thought is: Why not? For the small cost involved, why not put on a dissipator? You can't even buy a decent hand held GPS for the cost of one.
If you want to ground your boat, it still seems logical to me that you can use some South Island Ingenuity and just wrap your chain around the shrounds and toss the anchor over. If there is tension on it, it would seem a better conductor than plastic.
Just some thoughts.