The guy behind me in the anchorage that was hit a few years ago had just installed a complete "lighting system" including the fuzzy brush. I guess it did a good job of attracting old sparky.....
it does usually take the path of least resistance... all things being equal, if two boats are next to each other, and one of them has a well grounded mast and lightning protection system, and the other boat doesn't, the lightning will probably hit the boat with the lightning protection system, but likely do far less damage to the boat than if it had hit the boat with no protection.
That said, the use of the "fuzzy brush" is fairly common on cell phone towers above certain types of antennas to encourage the lightning from striking the antenna, and instead hit the huge grounded metal structure next to it, and they are reported to work quite well. Again this is a way of helping to direct the lightning bolt along the path you want so it doesn't choose the path you don't want, not a way of preventing a strike.