Keith Dysart wrote:
I am having great difficulty finding any difference
between my writing:

So it is your contention that "far from the antennas
it is "interference" that causes the variation in field
strength, but that on the line drawn between the two
antennas some other mechanism is responsible".

and your paraphrase.

The difference is that your example contained elements
that are not zero dimensions. My assertions covered only
antenna elements of zero dimensions. I repeat:

On a line drawn between two coherent isotropic radiators,
in the absence of any reflections, interference along
that line is impossible because the average total
power density all along that line is constant.
There is no interference in standing waves given
"interference" as defined by Eugene Hecht in "Optics".
--
73, Cecil http://www.w5dxp.com