For now, I still buy into the field theory version as discussed in "Grounding and Shielding In Facilities", Morrison/Lewis, 1990, pg 15
1.8 Field Concepts
All electrical energy is transported by electric and magnetic fields...Conductors do not carry energy-they simply direct where the
energy can travel. The idea that conductors carry power is a common misconception.
Fascinating but I can't buy into that. The size and shape of both the electric and magnetic fields are determined by the insulating media as observed through experimentation. That means that propagation rate down the wire would be determined by the insulation - which it isn't. Propagation rate of energy from end to end of a wire has been shown to be dependant on the material of the conductor; not the outside wrapping.
As stated in your link:
Whichever media controls the propagation rate must also be where the energy is located and moving.We cannot have a world that follows different rules at different times.
Einstein basically said the same thing. There needs to be one rule that describes both gravity and electromagnetic behaviour - the Unified Field Theorem. No one has yet resolved this so we, and they, can all be wrong on how it works.