CNEO-TST includes shallow tunneling. By "shallow tunneling" we refer to tunneling in which the tunneling energy is only slightly below the top of the effective barrier. Shallow tunneling can be understood in various ways, and one possible way is to make an analogy to path-integral-based theories because the delocalization of proton density across a barrier in CNEO is analogous to way that a Feynman-path-integral ring polymer 48 crosses a barrier top by slightly stretching the polymer and locating beads on both sides of the barrier.