Fiora Sunshine's post, Why I Transitioned: A Case Study (the OP) articulates a valuable theory for why some MtFs transition.

If you are MtF and feel the post describes you, I believe you.

However, many statements from the post are wrong or overly broad.

My claims:

There is evidence of a biological basis for trans identity. Twin studies are a good way to see this.
Fiora claims that trans people's apparent lack of introspective clarity may be evidence of deception. But trans people are incentivized not to attempt to share accurate answers to "why do you really want to transition?". This is the Trans Double Bind.
I am a counterexample to Fiora's theory. I was an adolescent social outcast weeb but did not transition. I spent 14 years actualizing as a man, then transitioned at 31 only after becoming crippled by dysphoria. My example shows that Fiora's phenotype can co-occur with or mask medically significant dysphoria.

A. Biologically Transgender

In the OP, Fiora presents the "body-map theory" under the umbrella of "arcane neuro-psychological phenomena", and then dismisses medical theories because the body-map theory doesn't fit her friend group.