  Distance-redshift data can impose strong constraints on dark energy models
even when the equation of state is oscillatory. Despite the double integral
dependence of the distance on the equation of state, precision measurement of
the distance-redshift relation for z=0-2 is more incisive than the linear
growth factor, CMB last scattering surface distance, and the age of the
universe in distinguishing oscillatory behavior from an average behavior. While
oscillating models might help solve the coincidence problem (since acceleration
occurs periodically), next generation observations will strongly constrain such
possibilities.
