[en] Attempts to reconcile a 17-keV neutrino with constraints from astrophysics and double beta decay have led to model Majorana neutrino mass matrices with vanishing (or nearly vanishing) electron-electron components. A simple parametrization is presented of the higher-order mass effects on the intermediate-state propagator through which 0ν ββ decay can still occur. For light-mass eigenstates, the 0ν and 2ν rates are proportional, with the ratio depending on a weighted sum over mass eigenstates left-angle m_ν³ right-angle _LL^Maj. Thus, model 0ν ββ decay rates can be predicted with confidence