This posting concludes my review of the literature in respect to ground and elevated radial performance at least for right now. I want to thank Al Christman, K3LC for his three part study and for adding to my knowledge base. His final investigation examined, what might be a typical vertical configuration, in a regulated community much like mine.
His article, A Study of Elevated-Radial Ground Systems for Vertical Antenna -- Part 3, was published in the May/June 2005 issue of the National Contest Journal. It was reprinted by the American Radio Relay League in the book, More Vertical Antenna Classics (2006).
Christman modeled a monopole radiator with either one or two radials using EZNEC Pro software, version 4.0, with double precision NEC4 calculating engine (2005). Additionally, the author measured soil conductivity as 0.005 Siemens/meter and dielectric constant (permittivity) of 13 for average soil in contrast 0.001 Siemens/meter and dielectric constant of 5 for very poor soil.
Christman (2005) operationally defined end fire as the elevation plane containing both the vertical and two horizontal radials. On the other hand, broadside is defined as the vertical plane in which the monopole is perpendicular to the end fire plane, according the article.
Christman later explained end fire as the plane in which radials reside whereas broadside is where no radials reside.
The author concluded that vertical systems with only one radial should not be elevated too far above ground. Furthermore, one radial outperformed that of two, because a single radial demonstrated slight directivity and front-to-back gain (2005). This may explain why DXpeditions typically deploy monopole systems with one slightly elevated radial. Lastly, according to Christman, one would want to think about soil type and height in respect to gain and take-off angle, as a function of antenna efficiency.
As a result of Christman's research, I learned there are far more variables influencing my antenna system other than standing wave ratio, as a means of determining antenna performance.
73 from the shackadelic near the beach.