@Nelemans05; @Webbink08]. Furthermore, the majority of the discovered double-degenerate systems have components of comparable mass, in contradiction to the results of past numerical work [@Han1998].

Recently, a reconciliation was attempted by instead considering angular-momentum balance, re-parametrizing the problem in terms of the so-called “$\gamma$-prescription” [@Nelemans00; @Nelemans05]. In this paper, we demonstrate that the $\gamma$-formalism is not stable against small changes in the binary parameters (§3), and that in general it too fails to provide a physical description of an initial, dynamical-timescale phase of evolution which is consistent with both energy and angular momentum conservation.

As an alternative, we remove the restriction to dynamical-timescale processes and consider the evolution of red-giant main-sequence (RG-MS) binaries via stable, but [*non-conservative*]{} mass transfer from the primary as the first phase of mass loss (§4,5). In this paper, we limit ourselves to systems where the initial primary has not reached the helium flash. We demonstrate that, upon the former secondary reaching RLOF, an ensuing CE phase will produce a set of DWD binaries with mass ratios and periods in line with the observed DWDs whose older remnant is $\la 0.46\,M_\odot$ (§6). Therefore the stable MT+CE channel provides a natural means for reproducing those DWDs in 