Bill Turner wrote:
2. The value of the coil at the base is smaller that a conventional
loading coil would be.

I'll send for the schematic but it sounds like he has
a resonant circuit at the base. If so, he has increased
the current through the coil considerably and losses
in the coil are proportional to I^2. Reducing the size
of the coil doesn't help if you increase the current
through it. Sounds like he is forcing self-resonance
in the coil by adding external capacitance. That
cannot be a good thing for efficiency. I'd like to
see his design up against a good screwdriver at a
75m mobile shootout.

Consider that moving a center-loaded coil to the base
of the antenna allows the coil to be made smaller but
the overall losses in the system increase considerably.
--
73, Cecil http://www.w5dxp.com