Just a few thoughts on the subject.

Lightning conductors are most accurately modelled as DC to HF transmission
lines - which indeed is what they are.

In addition to resistance they posses inductance, capacitance, a Zo and
propagation constants depending on length and diameter. It takes time for a
stroke to propagate down and along a set of conductors. It arrives at
different times at different places in the system.

The generator is a high impedance, pulsed current source of so many
thousands of amps. The voltage developed between a conductor, another
conductor, and what's in its environment is Zo times the stroke current.
Volts can leap across gaps.

Once in the ground current travels at a much slower velocity than along a
wire. Voltages developed depend on arrival times at different places. A
ground rod is a short length of line.

Frequencies of 100's of kilohertz are involved. Even reflected volts and
currents occur. Ground conductivity can be allowed for.

Very crude approximations are involved. Nevertheless, any information about
behaviour DURING a strike is better than none. It may be a matter of life
and death.

It would be interesting to calculate, for a given strike current, the
difference in voltage between the front and rear legs of a cow standing near
to and facing a grounded antenna mast.

Radio hams, presumably endowed with more common sense, can always wear
rubber boots while walking around their backyards carrying a field-strength
meter in thunder storms.
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Reg, G4FGQ