Because there is no physical test, no obvious symptoms, then it's in the mind - and if it's in the mind, and it's going to be covered by insurance (and like it or not that's the way our health care works, and given what the new laws say, it's going to continue that way - insurance companies are - and will continue to be - at the fulcrum point of medicine in the USA for a long time to come) it has to be in the DMS. That's a basic requirement for most insurance carriers. If they can't 'code' it on the billing, they ain't going to pay for it, and in that sense the DMS is a huge coding guide. And if your looking for insurance companies to adopt a more liberal, open and understanding attitude, then you haven't met many. They hire huge office complexes of people to avoid paying, not for trying to find new and novel ways to give the company money away. (Which is exactly how they see it.)
I guess if you have an argument with the use of the prefix 'trans' then, you need to pick a fight with the Dons of Oxford, as well as the Romans. Now count me in on the second, after all the Latin I was forced to take in school I have my own set of problems with them. If - on the other hand - your have trouble with how words come into existence in English, how they are validated and defined, and how they enter into popular usage, then count me out. Trying to change usage, though possible, tends to be like something out of Animal House, you know, a situation that absolutely requires a really futile and stupid gesture be done on somebody's part - and I'm not that person.
And, since this does seem a lot like attempting to create a definition of one (you) that does not cover everyone else (them), I'm not at all sure what my part in it would be as my basic response to attempting to define/explain/elaborate/educate myself, or any part of me is to tell the person that I'm not a library, I'm not 411, and I'm not their personal professor either. So the words used tend not to matter to me. I'm pretty much OK with being called anything except late for dinner.
I mean I feel you on that whole 'trans' thing, if I was forced to pick (which I'm not) I prefer crossdresser to transvestite, if a choice has to be made. Though I just call it 'doing drag' as that's' an old theater term/stage direction and I'm comfortable with that and everyone knows what it is. Transvestite , first off, is a big, old, pompous Latin-type word when crossdresser, the Anglo-Saxon description, is much more to the point. When any sort of alternative is offered, the modus operandi should always favor the Anglo-Saxon word, ceteris paribus. Good writing, Strunk & White assures us, eschews the Latin, knowing; Vox populi, vox Dei. Besides, crossdresser seems to center more on the fashion aspect, opposed to transvestite, which arises from the psychiatric community and basically defines a pathology of mental illness revolving around specific sexual issues. Transvestites are routinely presumed to be gay men dressing as women for the point of luring other men to have sex with them, or else straight men with a sexual fixation to the point of fetish - neither of which seems to fit me very well. And though I'm not 'doing a show' drag works for me because in a way (like the other public aspects of my life) is is a performance of a kind. But there you have it.
That, and I don't really believe in the psychiatric community either. So there is that too.