One way forward is to employ a local tensor, akin to a stressenergy tensor, that encodes both the vorticity and a gaugeinvariant kinetic energy in a natural way; 653 see also the current dependent meta-GGA form in ref. 654. This tensor furthermore obeys strong N-representability conditions that enable discrimination of regions with one, two, three, and four-or-more Kohn-Sham orbitals. The isoorbital indicators that underlie many standard approximations discriminate rigorously only between one and two-or-more orbitals. The absence of a strict Hohenberg-Kohn theorem is a problem not only for CDFT but also for spin-DFT, and, probably, also for DFT of superconductors.