help with becoming-rhizome

I’m having trouble figuring out how much of D&G’s rhizome v. arborescence, map v. tracing distinction is simply an ontological description and how much is a an affirmation of the rhizome over arborescence, mapping over tracing. Even on the purely descriptive level, there seems to be some ambiguity between arborescent models that are simply deceptive depictions of what is in reality rhizomatic – as the arborescent conception of the self and the workings of the mind is a factually incorrect depiction of the brain – and ones that have a very real life – as the arborescent model of sovereign power has a real historical life which can be contrasted with other, equally real, rhizomatic/nomadic power structures. On the level of an affirmation of one over the other, there seems to be a sense in which they are mutually constitutive: “the first [the root-tree] operates as a transcendent model and tracing, even if it engenders its own escapes; the second [the rhizome] operates as an immanent process that overturns the model and outlines a map, even if it constitutes its own hierarchies, even if it gives rise to a despotic channel” (Rhizome, 20). In this case, it might be perfectly well to affirm the rhizome on a personal level, provided one recognizes that there could be no rhizomatization (word?) or deterritorialization without arborescence and territorialization, that they cut through and pass into each other. Yet there are other areas in which D&G hold out hope for a total deterritorialization, or say that everything is becoming rhizome.
Part of my confusion may be due to the fact that I am conflating rhizomatization and deterritorialization and I’m not totally sure that that is fair – I’m not sure if becoming a body without organs, which I take to be the paradigmatic deterritorialization, is equatable with becoming-rhizome, which may just be another way to cut up and organize the BwO. Help here would be appreciated.
That said, I finished Thousand Plateaus thinking becoming a rhizome sounded pretty fun.