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Beginning with high- T_c cuprate materials, it has been observed that many superconductors exhibit so-called "Homes scaling", in which the zero-temperature superfluid density, ρ_s0, is proportional to the product of the normal-state dc conductivity and the superconducting transition temperature, σ_dc T_c. For conventional, s-wave superconductors, such scaling has been shown to be a natural consequence of elastic-scattering disorder, but  we show that when an analogous calculation is carried out for elastic scattering in d-wave superconductors, a stark contrast emerges, with ρ_s0∝(σ_dc T_c )^2 in the dirty limit, in apparent violation of Homes scaling.  Within a simple approximate Migdal-Eliashberg treatment of inelastic scattering, I show how Homes scaling is recovered. In addition, I a present a revised analysis where both axes of the original Homes scaling plot are normalized by the Drude plasma weight, ω_(p,D)^2, and argue that this represents a powerful new tool for classifying superconductors in terms of order parameter symmetry, as well as scattering strength and character.