  Self-consistent electronic structure calculations, for devices recently
fabricated and studied by Zhitenev et al. for capacitance spectroscopy in the
quantum Hall regime, demonstrate that reproducible resonances in the coupling
between adiabatically free edge states and isolated ``puddles'' of electrons of
higher filling factor under the gate proceed from an interference phenomenon as
the edge states bend upon entering and leaving the gated region. We note that
results of experiment and theory which we published earlier this year relate to
a similar, if not identical, phenomenon.
