Derek wrote:
"---give me a convincing argument as to why Art`s antenna should not be
viable,---."

It may be viable. Light bulb thansmissions have been detected over
considerable distances.

From clues, Art`s antenna is a full wavelength of small wire coiled to
make a dipole. If equilibrium means two equal coils are used to make the
dipole, each contains one half wavelength of wire. Each coil fits
(almost) in a shoebox.

Such a dipole doesn`t radiate as a fullwave antenna, although Art`s clue
is that his antenna doesn`t radiate perpendicular to the axis. That
would be true for a straight fullwave antenna remote from ground. Terman
says on page 868 of his 1955 opus:
"The result is a directional pattern in which the maximum of radiation
occurs at an angle with respect to the wire axis which is the case shown
in Fig. 23-6 is approximately 64 degrees (see Fig. 23-4a)."

I`d wager Art`s antenna radiates more as a halfwave dipole radiates.

I posted an excerpt earlier that said that experimenters had found a
short insulating whip could be wound with almost twice the resonant
length of wire to make the short whip resonant at about half the
frequency for a conducting pole of the whip`s length. British hams were
quoted as saying the results were good when heavy wire was used for the
coil. One can imagine making a dipole with two such quarterwave pole
lengths which is my guess as to what Art did, except for the heavy wire.

A continuous small diameter coil is a radial mode helix, not an axial
mode helix. It will radiate radially or perpendicularly like a length of
wire replacing the axis of the coil. Its radiating length is only about
half the length of wire wound into the coil using the experimental
results. A full wavelength of wire continuously loading a half
wavelength dipole would have about twice the loss resistance of a
straight wire dipole. This explains the wide bandwidth Art clains for
his antenna.

Efficiency is radiation resistance over total resistance, (loss +
radiation resistance). Radiation resistances for the straight and coiled
dipoles are about the same but the higher loss of the coiled antenna
makes it something of a dummy load. Low efficiency does not make such
antennas not "viable".

B&W has many satisfied customers for its resistance loaded folded
dipole. Bandwidth can trump efficiency. Art`s antenna may find similar
favor.

Best regards, Richard Harrison, KB5WZI