Harry Benjamin is probably most well-known as the guy whose name was in WPATH (the World Professional Association for Transgender Health) before they renamed it; it used to be the Harry Benjamin International Gender Dysphoria Association (HBIGDA). He was therefore the most influential of the trio apparently, despite previously promoting an anti-aging "fountain of youth" serum and an ineffective cure for tuberculosis, both using... turtle fluids (see image at the bottom)? Yeah, I have no idea. That sounds like something Staph would claim to be using in one of her hokey ass spells. Anyway, on top of being a snake oil salesmen, he alongside co-author Charles Ihlenfeld posited in
Transsexualism (1973) that the "normal" male "feels himself" to be a man (giving rise to nebulous "gender feelings" that we see so often), is heterosexual, and would be horrified at the thought of cross-dressing. The "normal" female "feels, looks, acts, and functions as a woman", is heterosexual, does NOT want to be anything but subservient to her husband, and dresses and makes herself up to be attractive to men. This is the foundation of the "gender binary" that queer theory troons loves to harp on about, and current gender dysphoria guidelines decree that anyone distressed by this exceedingly narrow view of male/female and man/woman is to be pathologized and treated through therapy, drugs, and/or surgery, rather than other measures.
If this was all that they hypothesized, it would be pretty standard sexism and homophobia (gender non-conformity and homosexuality tend to go hand-in-hand in childhood development) for the 1970s. However, what really gets me is their theory of what turns a fetus transsexual: the womanly hormones of the mother's body interfering with gender development in the womb. Seriously. They honestly believed maternal estrogen could "repress" the maleness of the fetus (but only sometimes) and make it "too feminine" or underdeveloped in its structure or chemistry, producing a transsexual child. Benjamin and Ihlenfeld then went on to say something about the feminization of the testicles, calling it an "incomplete expression" of "testicular feminization syndrome
" with the defect... only affecting the brain, leaving the actual testicles unscathed. As if phantom feminized testicles in the brain wasn't enough to turn a child transsexual, they also believed that mothers who "may not be able to handle aggressive and active play" and directed their boy children towards quieter activities and companions (namely girls) would cause them to troon out, because feminine behaviors were rewarded by their mother and other members of their family.
Their "research" rarely focused on hypothetical girl children because I suppose the hypothetical boy children were more important, but when it did, it once again does nothing but blame the mother for why her child is transsexual: from being emotionally unavailable or too depressed to parent her child, to somehow raising her child to be a surrogate husband because the father is a deadbeat, to teaching her child that being assertive and independent is a good thing, it all inevitably falls on the mother and nobody else. They also claimed that parents of transsexual female children believed their baby girls were "somehow less attractive, less cuddly, and more aggressive than her sisters’", because being ugly as a baby was enough to get you diagnosed with troonacy.
That explains why so many female troons are so ugly, I guess. Turtle fluids:
Edit: fleshed out a sentence.