  Dynamic dark energy (DDE) models are often designed to solve the cosmic
coincidence (why, just now, is the dark energy density $\rho_{de}$, the same
order of magnitude as the matter density $\rho_m$?) by guaranteeing $\rho_{de}
\sim \rho_m$ for significant fractions of the age of the universe. This
typically entails ad-hoc tracking or oscillatory behaviour in the model.
However, such behaviour is neither sufficient nor necessary to solve the
coincidence problem. What must be shown is that a significant fraction of
observers see $\rho_{de} \sim \rho_m$. Precisely when, and for how long, must a
DDE model have $\rho_{de} \sim \rho_{m}$ in order to solve the coincidence? We
explore the coincidence problem in dynamic dark energy models using the
temporal distribution of terrestrial-planet-bound observers. We find that any
dark energy model fitting current observational constraints on $\rho_{de}$ and
the equation of state parameters $w_0$ and $w_a$, does have $\rho_{de} \sim
\rho_m$ for a large fraction of observers in the universe. This demotivates DDE
models specifically designed to solve the coincidence using long or repeated
periods of $\rho_{de} \sim \rho_m$.
