I think I might grasp what you're alluding to here -- especially with regard to the social dimension of gender, and the interaction between biochemical input and gender realization -- but I'd very much like to hear what I assume will be your much more articulate assessment of what the Butlerian gender model leaves out.
I draw my understanding of Butler's view of gender primarily from her book "Gender Trouble" (available as an e-book), and "Performative Acts and Gender Constitution". (and yes, I have read her more recent book "Undoing Gender" as well)
In Performative Acts and Gender Constitution, Butler argues as follows:
Further, gender is instituted through the stylization of the body and, hence, must be understood as the mundane way in which bodily gestures, movements, and enactments of various kinds constitute the illusion of an abiding gendered self.(* an aside - this will not be a detailed dissection of Butler's paper *)
This is significant to me because it foreshadows Butler's view of gender as primarily existing as a social construct, to some extent influenced by biology.
Significantly, if gender is instituted through acts which are internally discontinuous, then the appearance of substance is precisely that, a constructed identity, a performative accomplishment which the mundane social audience, including the actors themselves, come to believe and to perform in the mode of belief. If the ground of gender identity is the stylized repetition of acts through time, and not a seemingly seamless identity, then the possibilities of gender transformation are to be found in the arbitrary relation between such acts, in the possibility of a different sort of repeating, in the breaking or subversive repetition of that style.
There is a surprising irony in Butler's position. On the one hand, she dances around the concept of Gender Identity as having an individual reality, and then settles in a place where she ultimately ends up rejecting the concept, subsuming it under the social and biological aspects of gender.
Because there is neither an “essence” that gender expresses or externalizes nor an objective ideal to which gender aspires; because gender is not a fact, the various acts of gender create the idea of gender, and without those acts, there would be no gender at all. Gender is, thus, a construction that regularly conceals its genesis.
The problem I have with Butler's model is that it fails to successfully encompass a few key aspects of cross-gender (and in particular transsexual narratives).
First, there is a common dimension to many transsexual narratives (not all, but enough to be significant) that includes an awareness of being "built wrong" from an exceedingly early age - often before any socialization or 'gendered behaviour' is evident.
Second, is the dyssonance that transsexuals express with regard to their lives in their pre-transition gender roles. If gender were solely a matter of social construct informed by physical biology to some degree, it becomes extremely difficult to square the model with the expressed dyssonance. In Butler's model, there is no room for dyssonance. In some respects, Butler appears to try addressing the issue as one of 'discontinuity', but she fails to appreciate that while a transsexual's pre-transition identity may be externally continuous, that is not the internal experience.
Third is the situation of David Reimer. I do not claim that Reimer was a transsexual - such was unquestionably not the case, but his case is important and revealing of some key aspects of transsexual narrative.
It is very significant that when John was being raised as Brenda, he fought against being treated as a girl at every turn. Physically, and to the best of his knowledge, John had always been Brenda - and yet refused to be Brenda - not just in respect to social aspects of gender, but was also horrified by what puberty would bring. (artificially induced or not)
From a transsexual's perspective, Reimer's narrative is undeniably consistent with the 'built wrong' narrative so common among the transsexual population. There is no doubt in my mind that this should be seen as independently validating the notion that gender identity may exist and is not fully informed by either social or physical cues. (as an aside, I suspect that where there are some interesting phenotype variations that are being identified among transsexuals in more recent years.
If, as Butler proposes, gender is defined primarily in the context of social and physical cues, then one might imagine that the John Reimer story would have had a much different outcome. As it is, eventually Brenda learned the truth of her history and chose quite consciously to transition to living as John. A train of events that substantially calls into question a model of gender which is based solely upon social and physical factors. (* Butler attempts to address John Reimer's story in Undoing Gender, however my reading of her on that matter leads me to believe that she fails to understand some key aspects of the situation. *)
Similarly, I do not believe that Butler's model explains the dissonance that so many transsexuals describe as overwhelming their pre-transition lives. Butler's model suggests strongly that if one's body is physically of one gender, and the social signals received are consistent with that gender, then everything should be good, right? So why is that transsexuals so consistently report something dramatically different? Further, why is it that therapists have found that transsexuals are generally not responsive to the kinds of corrective therapy techniques that work well in other situations where cognitive dissonance is reported?
Where I fundamentally disagree with Butler is in her rejection of the notion of an abstract, but essential attribute of 'gender identity' as distinct from our physical and social gender behaviours. The problem that Butler's model faces is in the narratives of thousands of transsexuals - and those narratives reveal a significant incompleteness which leads many radical feminist thinkers to engage in tactics such as erasure in order to sustain the perceived validity of Butler's model in the dimensions where it has greater strengths - namely in the understanding of the socially constructed aspects of gender.