  We examine the dark energy and matter densities allowed by precision
measurements of distances out to various redshifts, in the presence of spatial
curvature and (near) arbitrary behavior of the dark energy equation of state.
Degeneracies among the parameters permit a remarkably large variation in their
values when using only distance measurements of the late time universe and
making no assumptions about the dark energy or curvature. Going beyond distance
measurements to a lower limit on the growth of structure bounds the allowed
region significantly but still leaves considerable freedom to match a flat LCDM
model with dark energy very different from a cosmological constant. The
combination of distances with Hubble parameter, gravitational lensing or other
large scale structure data is essential to determining robustly the
cosmological model.
