I have a response for Eternally Learning; again I'm not sure about the previous few posts and what is on- or off- topic, I hope this is. Given EL's good faith discussion, EL's entitled to a response if interested. I've responded to a few sentences which I think are the substantive parts of the discussion and hope for some clarity between us, if not agreement. I respond both to some specific points but also to EL's more general question, about the possibility and desirability to bring minds in line with bodies rather than vice-versa.
[Transmen and transwomen] are intending to change their gender to be different from the one they were born with. A core part of each gender is reproductive ability and that is something that is currently impossible to attain. Therefore they cannot fully attain what they intend to attain.
S1) I believe this is correct.
S2) We might better say 'A core characteristic of each gender is reproductive ability, but reproductive ability is neither a necessary nor sufficient condition to be a man or a woman, even in the fullest sense'.
S3) I think you are mistaken about what 'they' intend to attain.
'Cis-' status is not an asymptote. There is no physiological trait which every person, and only those people, who are 'cis-' manifest; and which every person, and only those people, who are 'trans-', do not manifest (barring the neurological state which matches up with their dystonic experience of gender). If you had a big old box where you could filter every person through a 'trans' and 'cis' criterion you'd have two distinct populations, but they wouldn't be distinguished in the final instance on physiological facts (least of all reproductive ability). The -distribution- of physiological traits might be different between the populations, but there is no exclusive physiological marker. Do you disagree? If what I've just said is correct, then there are all kinds of bodies with all kinds of traits; it is not reasonable to assert that all those who are cis- are in possession of some material fact which all those who are trans- are not. It is thus possible that someone who is trans- satisfies more of your criterion for physical gender than someone who is cis-.
there simply are core and peripheral traits (physical and otherwise) which make up either gender and physical transitioning simply cannot attain all of them. . . . A mental transition would give a transperson just as much opportunity as a cisperson to have all the physical traits associated with their gender.
S1) None of those traits in themselves are either necessary or sufficient to be either gender.
S1) 'Attaining all of those traits' is not a metric by which the success of transitioning is measured, and there is no reason for it to be.
S2) What if someone who is infertile desires to manifest a fertile body - would a mental transition to bring their mind in line with the facts of their infertile body be appropriate?
The question of altering minds to bring them in line with bodies instead of altering bodies to bring them in line with minds is an interesting one. However, as it currently stands, people can articulate their dissatisfactions and their desires with their bodies. If I want a tattoo, I can recognize that desire and pursue it. I can articulate that and seek to remedy it as well. But what is the reverse scenario? Given Body X, how do you know what changes to make to the brain to bring it in line with that body? The hypothetical is too thin in detail to be evaluated - what specifically will be changed? If I experience significant dissonance about my physical sex, I feel you're going to have to determine where that dissonance comes from (whether bio-, psycho-, or social- causes) before endeavouring to mitigate that dissonance through neurological intervention.