Attractive potential ordering does not order quantum reflection

For a square well of width $L$, exterior wavenumber $k$ and interior wavenumber $q>k$, matching the wavefunction and its derivative gives the reflection probability $R=C{\sin }^2(qL)/(1+C{\sin }^2(qL))$, where $C=(q^2-k^2{)}^2/(4k^2{q}^2)$. For example $q=3k$ and $kL=\pi /2$ give $R=16/25$, whereas zero potential gives $R=0$. Moreover deeper wells at $qL\in \pi \mathbb{Z}$ have zero reflection by resonant transmission through a square well. Reflection therefore cannot be ordered solely by pointwise ordering of attractive potentials.