A further gap is the distinction between 'valley branching' and VRI points. This is not correct. Singular NTs unambiguously define the branching . There is an illustrative introduction to the higher dimensional case . For a PES with more than two (toy) dimensions manifolds of VRI points arise . If the PES is symmetric, the VRI manifold often forms a symmetry hypersurface. However, asymmetric VRI manifolds can also be computed . Recently, the role of VRI points in dynamical processes has been discussed .