this limit means that the star is as small as $\sim 2.6\,R_\odot$ and has barely left the bottom of the giant branch). In [@Sluys2006], it was adopted that all stars beyond the bottom of the giant branch will start unstable MT (see their condition for instability 7), so the detailed MT calculations were performed only for stars that have not become giants yet upon reaching RLOF. We note that in both studies the donors could become giants after the start of the MT and continue MT stably, but the initial conditions limited the donors at the end of the MT to rather early giants.

An alternative formulation, in which the envelope of the initial primary is lost without significant spiral-in, was formulated in terms of a new parameter $\gamma$ (see §\[sec:2.1\]). It was found that $\gamma=1.5$ allows for widening or very mild shrinkage in the first CE phase (for mass ratios very close to unity) but extreme shrinking in the second. As a result, it has been claimed in [@Nelemans05] that this single value of $\gamma$ can explain [*all*]{} observations and therefore can be used to predict the outcome of a CE, as well as any other dynamical-timescale evolution, for 