I am reading "Healing the Fragmented Selves of Trauma Survivors: Overcoming Self-Allienation" by Janina Fisher, 2017, at the moment. I can really relate to it. It doesn't make much distinction between levels of dissociation (i.e. DID vs non DID). It's all the same cause, its all pretty much the same internal process, and its all treated the same way. Brilliant book. I highly recommend it.

Just wanted to add I was diagnosed with DID by my previous psychologist in conjunction with a psychiatrist, then referred to my current psychologist when my ex psych left her practise because my current psych has more experience with DID. And she does, my current psych is good at what she does and treats several clients with DID.
But I learned recently that my current psych doesn't actually care for diagnostic labels at all, so although I "officially" have the diagnosis of DID she doesn't like to call it that at all. She just refers to my "symptoms" as normal results of trauma. As in "this is how human beings develop when they develop under traumatic conditions". She does not treat a "disorder" or a "mental illness". She has told me repeatedly that she treats the psychological injuries of developmental trauma.
So I guess in that context or lens I do not "have" DID at all.