[Lenneth]

After giving this whole subject some considerable thought, purely out of curiosity and a wish to make sense of it, I currently have this train of thoughts:

Although I do believe that there is a continuum from 'totally male' to 'totally female' and that the in-womb hormonal balance plays a big part in defining where we are on that scale, there must be more to it than that. As AbiDrew said, she prefers to think of it as a cloud and thats a pretty good way of putting it, I've said '3-D' myself, in the past, but even that is too rigid.

Soooo, I suspect that one/some of these other factors may be what tips an individual over the edge into being an all-the-way TS, even if the in-womb environment is what starts it. The basic logic behind this thought is that there does appear to be three distinct sets of effect from males taking female hormones, in whatever form: (a) Fully male males, get really upset, screwed up and generally react badly.(b) Some (the majority of us here) get a general sense of well being, reduction in stress, etc, and also a surprising reduction in the need to cross-dress and other female type interests. (c ) Some suddenly feel liberated, even more female and realise that they do indeed want to go all the way.
(a) Is logical and what we might expect and we can ignore that.
(b) Makes sense for the simple 'inbetweenies' who's brains expect a level of femaleness that their male bodies can't provide
(c ) There must be some other factor(s) involved to bring this fairly extreme need, to the surface, although I have no idea what they may be.

So, I don't think the term 'brain re-wiring' is correct. Re-wiring implies physically changing what is there now into something different. What we are actually doing is probably more a case of re-balancing - think of steering wheel judder that magically disappears if you get the wheels re-balanced and the whole car suddenly feels smoother and more comfortable. Maybe for TS's, they actually need not just a re-balance but a whole new set of tyres?

wow, talk about a nail hit squarely on the head.

I doubt it could be described better.