because we are talking very small figures here - less than an ohm.

If water was such a bad conductor,  we would't have all these faults due to damp etc, and we could fit any IP rating outdoors  

A socket circuit in a standard house - max Zs 1.2, usually half that!

water has a high resistivity compared to metals and the resistance of water in a 1m long domestic pipe is therefore generally high enough to be safe even with addatives in the water.

with your wet wall its not just a straight line down the wall its a huge triangle of wall from your socket to the ground (plus some effects from bits of the wall outside the triangle)

wires cables and pipes have a much larger length than any other dimension this means we can reasonablly approximate them as a wire with a perfect contat to both ends that covers the entire end.

with other shapes of objects the calculation gets much harder.

I thought he was saying you CANT compare it to the research done with pipes ???