  We perform a systematic analysis of single-channel quantum interference in
laser-induced nonsequential double ionization with few-cycle pulses, using the
strong-field approximation. We focus on a below-threshold intensity for which
the recollision-excitation with subsequent ionization (RESI) mechanism is
prevalent. We derive and classify several analytic interference conditions for
single-channel RESI in arbitrary driving fields, and address specific issues
for few-cycle pulses. Since the cycles in a short pulse are no longer
equivalent, there are several events whose dominance varies. We quantify this
dominance for single excitation channels by proposing a dominance parameter.
Moreover, there will be many more types of superimposed interference fringes
that must be taken into consideration. We find an intricate tapestry of
patterns arising from phase differences related to symmetrization, temporal
shifts and a combination of exchange and event interference.
