It can be shown that the coupling strength corresponds to the degree to which the bands bend away from each other, almost as if the bands are exerting a "repulsive force" to one another that increases away from the point of band inversion (Figure , see Section 5.2 for further details). We test this computationally by tracking the curvature of the Γ + 4 conduction band edge in rocksalt SnSe (even parity) while artificially raising the energies of the secondary Γ - 4 and Γ - 5 ⊕ Γ - 6 conduction bands (odd parity) using a nonlocal external potential (see Section 5.3.3 for details on the computational method). The resulting band structure after applying a potential of ∆V = 5 eV is shown in Figure . We find that the curvature of the conduction band edge gradually transitions from negative (warped) to positive (parabolic) as the energy separation between the band edge and secondary bands becomes larger (Figure ). Since the energy separation of the band edges at the L-point is rather unchanged (Figures and), the transition is not due to the degree to which bands are inverted as in Figure . Rather, the warped-to-parabolic transition can be largely attributed to isolating the even-parity Γ + 4 conduction band edge state from the odd-parity secondary conduction bands.