If so, how?
the only way your gonna convience me that it has any effect on helping lightning find it's way to the ground is that if the dog in question is full of or has a great amount of Salt, then it may persuade lightning to be attracted to it. When I was young we tried some crazy things and one of them was tring to use lightning to disturb school so we could all go home. Well we found out that to influence lightning we would bury a 20 pound bag of salt at the base of a light pole, then it was a magnet to ground and would only raise the slight chance that it might be a hit. Such is stupid things kids do.
One could assume that is a big dog (like a human person) is running on a and open field during thunder storm, it could be hit by a lightning and if tail would be on higher position, the lightning could srike there.