This moves a little way to looking at the importance of identity, both personal identity conception (internal) and other parties' identity acceptance (external), through the experience of a MTF person's genitalia; the same ideas might apply to a bisexual person who wants better coincidence between how they themselves and the rest of society views their identity (both the part of which is internally determined and the part which is governed by the manner in which one is seen by one's lover/family/community/country - or whichever arena matters most to the person - not therefore including the consequences of this recognition or seeing-act, e.g. being granted rights, equality. etc.).
A person might feel pansexual inside, but be read as straight or gay, which is distressing when one has worked so hard to be able to own one's pansexual element of their identity, especially if their sexuality is a major part of their identity in their opinion, as mine is for me. I feel that it diminishes the validity of my identity when my pansexual status is called into question - either by someone reading me incorrectly, declaring to my face that there is no such thing as bisexuality/pansexuality, ignoring bisexual needs during discussion/advertisements that concern queer matters. My identity is diminished because there is doubt that what I am believing/thinking/feeling/
Denying bisexuality within 'discourse' by which I mean the combination of all word output (written/spoken) - either by literally denying it exists or limiting its prominence/voice by not giving it column inches/airtime, might make some, and it sure does make me, less willing to own and represent the identity of bisexuality. It isn't seen as an option and/or it isn't seen as important - so I should either quieten down my desire to be known as a bisexual or I should reassess whether I really am one. In communities where no-one has heard of homosexuality, no-one is going to think of themselves as a gay person - they may have feelings/urges but they cannot name them as being part of an identity. When there is finally a gay newsletter or tv show, the person can begin to form the identity of a gay person, they can now comprehend their feelings within a context where an explanation (homosexuality) is given, they can know themselves as a gay person, now that they know what gay is and have words to describe themselves. Having the language, label and place in discourse is essential for being able to have the identity of the minority - if there is no naming, then the minority are just a (confused/unhappy) subset of the population, rather than having a distinct element to their identity.
If someone wanted to leap off a bridge attached to something secure and feel themselves bounce up and down, they would find these urges strange and be unable to identify that part of their identity until they were introduced to bungee-jumping and the term became part of the vocabulary, was seen in newspapers, was used on tv, etc. They would then be bungee-jumping enthusiasts.
Space in the discourse gives an individual the permission and space to identify themselves in the manner they choose, if their choice is to identify with something which is not the norm (those that think that they fit in with everyone else don't need specific space, the rest of the discourse would fit them). If this space was removed/halted/minimised, the person would feel that their long-sought-after identity is being dismantled - that it wasn't being permitted or recognised and thus maybe was no longer valid. The validity of this element of one's identity might be based on permission to name or talk about it, or the majority of society's acceptance of it, or just the acceptance of key people (parents, lovers, etc.) - it's probably different for different people. For me, having advocacy groups and LGBT commentators fail to recognise that bisexuals should be mentioned in marriage equality advertisements is distressing. It is also annoying that there is no better word to describe marriage/partnership between two women than 'lesbian' and between two men as 'gay', because those adjectives are meant to describe the union of two same-gendered persons, yet they also connote that those involved would identify as gay or lesbian, which is clearly false in the case of two bisexual women happening to end up together. The description of the gender expressions of the two involved should not also be taken as a description of their sexual orientation, but that seems to be what is happening.
If one were to say Jim and Jill are in a relationship - you would know that those two people are in a relationship, that one is probably male-identifying (Jim) and one female-identifying (Jill) and the majority would assume that they are heterosexuals.
Simple assumptions. What if the names were not gender obvious/suggestive? How might a commentator describe that scenario?
If one were to say Jean and Jean are in a relationship - you would know that two people sharing the name Jean were in a relationship - I would wager that a (smaller) majority would assume that they were of two genders and thus heterosexual. If one were to say Jean and Jean are in a lesbian relationship - you would know that two people sharing the name Jean were in a relationship where both partners self-identify as female, yet an (even smaller) majority would assume that they were lesbians. The speaker may only want to convey the gender of the couple, not their orientation, yet there is a paucity in the language to allow us to describe one and not the other.
What if they were both bisexuals? Saying that Jean and Jean are in a bisexual relationship tells you that they are what exactly? Together but open to other gender-options, without stating what gender the protagonists express... Or perhaps it suggests something confusing about the participants' gender expression - perhaps one plays both male and female roles during the relationship... Or perhaps that they are polyamorous/swingers... I hate to say it (as I believe in strict monogamy) but the terrible misunderstanding about pansexuals is that they are willing to participate in threesomes/open relationships - I'm not sure when 'not minding about the packaging, especially in the primary/secondary sexual characteristics, it's all about the person inside' became 'I'm interested with having relationships/sexual-romantic experiences with multiple people of multiple gender-expressions contiguously'.
So to describe a lesbian relationship is to primarily categorise the participants mostly by their gender expression and probably to a large extent their sexuality orientation, too...
to describe a bisexual relationship is to say nothing about the participants' gender expression but to suggest something unusual/unsavoury (in my straight-laced opinion) about their sexual orientation, desires and practices.
I wish we could hurry up and develop language that delivered the exact message we want - either describing gender expression, sexual orientation, both or neither! Maybe we could say Jean and Jean are in a successful relationship and we'd all just cheer for them!