By and large, Keenan seems to try to avoid taking a position. I suspect this is simply a matter of avoiding the truth. I know I had to face this question during my transition. In my case, I quickly realized that there are a lot of men who such as those Keenan describes:
The guys I go out with self-identify as straight. In fact, a number of them were in heterosexual marriages previously and fathered kids. Yet, they are attracted to me. And this happens a lot. Meaning, it's widespread and common -- at least in my experience.Now, they may claim to be straight, and some of them may really, really believe they are. Shoot, a lot of men who wanted to date me were married. I would wind up politely declining, but I found this strange. But I also quickly realized these men were not really interested in me, but were wanting to date a "woman with a penis," to put it nicely. I was just a fetish for them.
Were they gay? Perhaps not in the sense that the term is usually used, but they were certainly clearly interested in a homosexual relationship. I suppose some could be called bisexual, though many of them made it clear that they did not want me to pursue surgery. It did not take too long before I simply stopped dating until after my surgery.
Since my surgery, no one I have had sex with has known my past. I was not interested in dating a man who was interested in me because I had a penis. If I had really believed they were able to see past that, I would have felt differently, but I quickly realized that was not the case.
Keenan tries to fudge and suggest that we either need to redefine heterosexuality to ignore the issue of body parts (heteroflexible?), or perhaps abandon the concept of sexual orientation labels. I would offer a simpler solution...face the fact that the men who are pursuing you are doing so because you have a penis, and decide if you like that (in which case you are not transsexual and should probably not have surgery) or that you don't (in which case celibacy until being post-op is the only viable choice). But telling yourself that this men really, really see you as a "real woman" is delusional.