It is often tempting to think that a few ground rods (ground electrodes in NEC parlance) can simply absorb all the energy of a lightning strike. But this is far from reality - each rod experiences "ground saturation". So while your grounded Polyphaser will hopefully direct a great deal of the lightning energy to its local ground rods, there will still be ample energy looking for alternative routes to ground that isn't saturated. The same is true for lightning coming in via your service connection, telephone line, satellite dish, CATV line, etc.
Large, commercial tower operations have an extensive grounding system network with many ground rods, radials and a grounding ring at the base of the tower to help distribute and absorb most of the lightning energy. Because it is well distributed, it does not reach ground saturation as easily during a lightning event. The result is that this will greatly reduce, but not completely eliminate, the amount that must be dealt within transmissions lines, the building and the communications equipment.
- Glenn W9IQ