Can feminism avoid being trans exclusionary?

A few months ago some of us discussed Julia Serano's book Whipping Girl, which argues that a lot of mainstream feminism ironically enforces the Aristotelian view that masculinity is healthy and normal and femininity is artificial and harmful. The chapter on gender in Tristan Garcia's Form and Object makes a similar argument with respect to some academic queer theorists who (according to Garcia) end up excoriating people who don't cowboy up and take responsibility for their own gender.

If there is a problem here it has to do with a calim that is taken to be almost analytically true in many Women and Gender's Studies classes. It goes like this. The division of sexes is a biological notion, and hence tied up with nomic necessity in some manner, while gender division is merely cultural, and hence highly variable and contingent. But the biology doesn't really support the presupposed views about biological sex (there are more than two genetic sexes, and the leap from genetic to genital sex requires at the very least lots of epigenetic factors we don't understand, and there are more than two genital sexes). And the view of gender as entirely cultural involves systematically ignoring what a lot of transgender people such as Juliana Serano have to say about their experience (and perhaps some of the relevant biology as well).

A recent post by Andrew Sullivan chronicles how this debate has gone beyond academia and is actually become poisonous in the activist community, pitting trans exclusionary radical feminist ("TERF") activists against transgender activists.

When Mark Silcox and I were doing research for the feminism chapter on our video games book (especially with respect to claims about three waves of feminism), we were struck over and over again just how difficult the following issue is for feminist theory. There's always a danger in feminist theory of reinstating the very forms of oppression that are being theorized about. And the danger characteristically goes like this. On the one  hand, one can end up unintentionally telling women they need to just be more like men (Serano and Garcia's charges have been made against earlier forms of feminsm as well). On the other hand, there's the danger of valorizing gender differences in a way that is in reality just Aristotle with condescendingly nice sentiments attached (Carol Gilligan and Carol Glover arguably both end up doing this). This issue about TERFs reinforces my belief that credibly negotiating this Scylla and Charibdis is almost an a priori success condition for feminist theory.

I'm about seven years out of date on this scholarship, and I never was a specialist, so it would be helpful to me (and I'm sure many readers) if anyone has any references to recent work that would negotiate the two dangers, especially with respect to the controversy in the activist community that Sullivan chronicles.