  The superconductive and magnetic properties of charge$-$compensated
(Ca$_x$La$_{1-x}$)(Ba$_{1.75-x}$La$_{0.25+x}$)Cu$_3$O$_y$ (normally denoted as
CLBLCO) are considered through quantitative examination of data for electrical
resistivity, magnetic susceptibility, transition width, muon$-$spin rotation,
x$-$ray absorption, and crystal structure. A derivative of LaBa$_2$Cu$_3$O$_y$,
cation doping of this unique tetragonal cuprate is constrained by compensating
La substitution for Ba with Ca substitution for La, where for 0 {\le} x {\le}
0.5 local maxima in T$_C$ occur for y near 7.15. It is shown that optimum
superconductivity occurs for 0.4 {\le} x {\le} 0.5, that the superconductivity
and magnetism observed are nonsymbiotic phenomena, and that
charge$-$compensated doping leaves the carrier density in the cuprate planes
nearly invariant with x, implying that only a small fraction of superconducting
condensate resides therein. Applying a model of electronic interactions between
physically separated charges in adjacent layers, the mean in-plane spacing
between interacting charges, {\ell} = 7.1206 {\AA}, and the distance between
interacting layers, {\zeta} = 2.1297 {\AA}, are determined for x = 0.45. The
theoretical optimal T$_{C0}$ {\propto} {\ell}$^{-1}${\zeta}$^{-1}$ of 82.3 K is
in excellent agreement with experiment ({\approx} 80.5 K), bringing the number
of compounds for which T$_{C0}$ is accurately predicted to 37 from six
different superconductor families (overall accuracy of {\pm}1.35 K).
