I worry that with a hegemonic term like "transgender" that erases the distinctiveness of TS, we will be the ones whose issues are "left behind" because ours are the most difficult (and expensive).
No more than the phrase "women of color" takes away from the experience of African-American women in America, nor does it erase the distinctiveness of the Hispanic women in America. Its just saying that there are common parts of the experience of both that they can make common cause. You can be European which doesn't take away from being Dutch or Greek - not all of which have the distinctiveness of being from either Amsterdam or Athens (both of which very different experiences in many ways.)
As for the binary sexandgender deal, yeesh, part of what I love about not being in academia is not having to talk like this. Gender is in several key ways different from sex, which is a strictly observable deal. In the sense that you 'sex' young chicks, you do not 'gender' them. Gender has to do with a range of traits - not necessarily exclusive to one or the other - where sex has to do with one aspect only, reproductive organs - a hole or a pole deal. "Sex" was, and is, a perfectly valid distinction for describing a given attribute, where "gender" was needed to elaborate on things, most of a a behavioral and psychological and cultural nature that were differences, not distinctions. (In the sense where you KNOW the split based on a distinction, but could only GUESS on the split based on differences alone.)
To the degree that moving from one to the other tends to reinforce the notion that there are two - the matter of the moving from one to the other proves that the wall between the two is not nearly as solid as once thought - it's not an absolute. Proving that the two are not absolute, is the first step to proving (or defining if you will, most of this is construct and not reality) that more than two are possible.
PS, its my understanding, poor though it is at such things, that "FTW" means "For the Win" in gammerspeak.