@User: I am fairly confident that the SkyWater Calibre decks give reasonable values for parasitic capacitances. The technology LEF views we got from SkyWater for the digital standard cell libraries were just plain wrong, as @User noted. A field equation solver would give more confidence in the Calibre equations, but my confidence was high enough to use some Calibre runs to determine the correct coefficients to use in the technology LEF files and the Magic technology file.