parallel paths via metallic services bonded to neutral at each property will certainly reduce the voltage gradient along the road - even a mere 15mm dia water pipe is equivalent copper area to more than a 25mm meter tail. However, current through the earth itself, in comparison, will be small and almost negligible. When you hammer in an earth rod, even 8 feet of one into soft Essex clay, you still see tens of ohms of Ze. A 4ft rod into sandy soil, and you will get more than 100, maybe 200 ohms. This will support currents that hurt but will not blow any fuses worth mentioning

Compared to the hundreds of milliohms of the copper and steel paths, the earth path in parallel is almost insignificant.

Also, most of the volts are dropped within one rod length of the electrode, as that is where the current density is highest- hence the step voltage risk to animals, and advice to either insulate the top foot or so, or to bury the rod, or to fence it off  for a few feet all round .

In reality around a traditional rod, on PME a small carrot shaped region of earth around the electrode is pulled up to the local neutral voltage, and the region of influence dies away very rapidly, and that is more or less it. The neutral to earth voltage (and I mean Terra firma earth, not some bit of G/Y string connected to the neutral) can be tens, but is usually single figures, as 3 phases conspire to at least partly cancel.

parallel paths via metallic services bonded to neutral at each property will certainly reduce the voltage gradient along the road - even a mere 15mm dia water pipe is equivalent copper area to more than a 25mm meter tail. However, current through the earth itself, in comparison, will be small and almost negligible. When you hammer in an earth rod, even 8 feet of one into soft Essex clay, you still see tens of ohms of Ze. A 4ft rod into sandy soil, and you will get more than 100, maybe 200 ohms. This will support currents that hurt but will not blow any fuses worth mentioning

Compared to the hundreds of milliohms of the copper and steel paths, the earth path in parallel is almost insignificant.

Also, most of the volts are dropped within one rod length of the electrode, as that is where the current density is highest- hence the step voltage risk to animals, and advice to either insulate the top foot or so, or to bury the rod, or to fence it off  for a few feet all round .

In reality around a traditional rod, on PME a small carrot shaped region of earth around the electrode is pulled up to the local neutral voltage, and the region of influence dies away very rapidly, and that is more or less it. The neutral to earth voltage (and I mean Terra firma earth, not some bit of G/Y string connected to the neutral) can be tens, but is usually single figures, as 3 phases conspire to at least partly cancel.