Comment on Density functional theory is straying from the path toward the exact functional

Medvedev et al. (Reports, 6 January 2017, p. 49) argue that recent density functionals stray from the path toward exactness. This conclusion rests on very compact 1s(2) and 1s(2)2s(2) systems favored by the Hartree-Fock picture. Comparison to actual energies for the same systems indicates that the straying is not chemically relevant and is at best specific to the studied dense systems.