It also blows up the lies of people who claim that transsexuality is just a late 20th century-21st century phenomenon.
from Clinical Sexuality, a 1974 book by John F. Oliven, MD
The milder case of transvestitism does not come easily to medical or any other professional attention, and it has rarely been included in the reports from clinic now specializing in transgender research.
From the 1979 Newsday article on Christine Jorgenson reprinted in the Winnipeg Free Press
As a young man, Jorgensen experienced strong emotional attachments to two male friends, but she says those feelings were never expressed. She admits now that she wasn’t entirely candid in the book. She did have “a couple” of homosexual experiences before she went to Europe to seek a medical solution to her problem, but they only reinforced the feeling that she wanted to relate to men as a woman, not as another man. “If you understand trans-genders,” she says, (the word she prefers to transsexuals), “then you understand that gender doesn’t have to do with bed partners, it has to do with identity.”
There's some fascinating stuff here that Cristan continues to add to at this transgender research link.