the 2-T models are statistically acceptable, and there are significant reductions chi-squared values in 8 cases (statistically justified at $>95$ per cent according to a likelihood ratio test).

Little weight should be attributed to this. It has commonly been found that multi-temperature fits are required to fit coronal X-ray spectra once a sufficiently precise spectrum is obtained. Even then, a 2-T model is probably a crude approximation to the true differential emission measure (DEM). The pattern here appears to be that the DEM could be approximated with a 2-T model with a lower temperature $T_{1}\simeq 0.6$keV and an upper temperature $T_{2}\simeq 1.5$keV. In spectra with insufficient counts or where one component is significantly larger (in terms of the number of X-ray photons produced) than the other, then a 1-T fit is adequate with $T_{1}<T<T_{2}$. The relative emission measure of the two components reveals that those 2-T models for which $T_{2}$ is unconstrained are where the cooler component is dominant.

Perhaps the biggest difference between the 1-T and 2-T models is that adding the extra [mekal]{} component relaxes somewhat the requirement for a very low metallicity in the 1-T fits. Even so, significantly subsolar metallicities are implied by all the 2-T 