to be fair, he’s offered a number of models, but to be equally fair, these models are based on assumptions without enough evidences/transitions/intermediary examples to concretely state the processes happened such and such a way. The evidences he’s presented are intriguing, and present a semi plausible mechanism provided the major hurdles facing evolution in other areas can be explaiend away- which biologically, they can’t unfortunately- or at least without itnroducing lateral gene transference, which I might add has it’s own insurmountable problems
Natural Selection is not a metric, since it has no mathematical value, therefore, it must be a mechanism, which it is according to the theory, and as such, it is required to describe and explain physical phenomena. This is simply fundamental to a scientific theory.
I don't care how much supposed evidence there is for this or that, or what reasonable intuition may tell one about the state of affairs of biological entities on this planet. The bottom line is, if you can't even establish the fundamental requirements of the structure of a scientific theory, then you just don't have one, it's that simple.