John S wrote:

There can be a lossless resistive part of source impedance according to
the IEEE (and most every other well educated EEs). After all, a
transmission line has a resistance but it's loss resistance is much lower.

Nope, a transmission line has a characterisic, or surge, impedance, not
a resistance.

There is a big difference between a resistance and an impedance.

The characterisic impedance of a transmission line is the square root
of the series impedance per unit length divided by the shunt admittance
per unit length.

See any electromagnetics text.

--
Jim Pennino