Ian, GM3SEK wrote:
"I am trying not to be biased about the actual problem - "

Open minds consider arguments.

Wave velocity = frequency x wavelength

Wave velocity in free space is 186,000 miles per second (300,000
km/sec).

Velocity of disturbances on open wire transmission lines is almost equal
to that in free space.

At high radio frequencies, a wavelength may be measured in inches and
centimeters. A transmission line containing a discontinuity produces a
reflection from the change. As a short distance can produce a phase
change of 360 degrees, the incident and reflected waves can combine to
produce voltage variations along a short line length. These can be
measured using simple instruments with confidence.

Circuit theory works on transmission lines because the proximity of
their conductors causes an effect on one conductor to be instantaneously
imposed on the other.

A transmission line cannot be analyzed as a simple series circuit
because current in the wires is not everywhere the same. Volts and amps
vary along the line depending upon construction, length. and load placed
on the line.

The line`s resistance, inductance, conductance, and capacitance are
distributed and accumulate with its length. In a wave in either
direction on the line, the volts and amps at any point on the line
conform to Zo but also depend on summation of the incident and reflected
waves at that point. Current in the linee is not independent of the
voltage.

A transmission line of any length terminated with an impedance equal to
its Zo has an input impedance of Zo.

Distribution of volts and amps on lines terminated with loads other than
Zo has been demonstrated countless times and is well understood.
Directional couplers are capable of separating forward and reverse
directions on a line, and are also well known, understood and have
proved useful. The Bird wattmeter uses a directional coupler, works as
advertised, and may be inserted anywhere in a 50-ohm coax line.

Best regards, Richard Harrison, KB5WZI