It used to be clearer years ago, there was more of a clearer division based on sexual orientation (I say it was clearer, because ten years ago you would not have heard a transsexual call themselves transgender, but now some do, but that may be more of a bandwagon thing).
It is true that (male-sexually-attracted) transsexuals are the group more likely to have genital surgery, but there was always that sub-set of the male-sexually-attracted males that did not (ie the L*boys), of which TH seems to be one (very proud of 7" surprises). Of course there were other subsets in the gay community that still thought of themselves as men/male; drag queens.
Transgender males are in the majority, sexually attracted to females. A small percentage of those may have genital surgery. Some are A*P, in fact, there is a touch of that in some TS.
Basically I don't fully go along with Blanchard, but he was onto something by trying to classify categories. I think the problem lies with trying to make them absolute categories, when in reality there are some shared grey areas going on.
And "OS" transsexuals can be just as misogynist as some of their gay male buddies as well. ie they don't get a free pass on misogyny just because they are gay males or transsexuals. So whenever I hear the "OST" on this board, I cringe.