You Are Right and I Was Wrong: Reply to Tailcalled on Causality
Summarizing—Ozy had claimed that the concept of autogynephilia is conflating three things: ordinary female sexual behavior (cis women also have female bodies in their fantasies!), a manifestation of gender dysphoria, and "true" autogynephilia without concomitant gender issues.
I was, and am, intensely skeptical that these are really three separate things. I think it's more parsimonious to suppose that some males are autogynephilic, and that some fraction of them go on to develop sex dysphoria, rather than to posit different causes for what really looks like the same erotic phenomenon depending on whether the person goes on to transition or not. But at the time, I didn't have the language to properly articulate the theoretical basis of my skepticism. Frustrated by the tendency I perceived of many trans advocates to resist scientific generalizations about psychology while acknowledging the empirical correlations that motivate the generalizations, I wrote, "Summarizing correlations is the entire point of making a taxonomy."
But as Tailcalled's response points out, this is just wrong! Different causal theories can generate the same correlations in a particular set of observations, while still making meaningfully and drastically different claims about the world.
As an illustrative example, suppose you observe that among professional athletes in Chicago, basketball players wear red jerseys, but gridiron football players wear navy-blue jerseys. Reifying these observations into a two-type "basketball/red" and "football/blue" taxonomy of professional athletes is perhaps not the worst theory—it does compress the length of the message needed to describe your observations—but it's definitely not a good one, largely because it's so fragile: it completely breaks down the moment you leave Chicago, or the Bulls unveil a new jersey, or you just look at what the visiting team is wearing. And it's fragile because it doesn't reflect what's "really going on" in the world: in fact, what color shirt you're wearing doesn't causally affect what games you can play, and vice versa.
In the case of sex dysphoria in developmental males, I think the documented correlations between age-of-onset, sexual orientation, history of female embodiment fantasies, &c., do reflect distinct taxons in what's really going on in the world. (If I only get one table to showcase the correlational data, I'll pick Table VI from Anne Lawrence's "Sexuality Before and After Male-to-Female Sex Reassignment Surgery".) I think alternative theories that try to explain the same bimodality in the data, such as Veale, Clarke, and Lomax's identity defense model (which chalks up the difference to whether or not defense mechanisms are used to suppress a gender-variant identity) are a stretch.
But I'm making that scientific judgment between theories based on my own parsimony intuitions applied to everything I've read and seen; convincing someone else who doesn't already think the same the way is, and should be, a lot more work. Trying to get away with "You agree to the bimodality, therefore you must agree to the taxonomy" would be both lazy and wrong, and I thank Tailcalled for his vigilance.