Not, I beg of you, a case of mistaken identity. Do you recall the scene where Lucy Snowe plays the role of a man in Madame Beck's Pensionnat? I think it is important to show us Lucy's personality, because why include this irelevant scene? I doubt that Charlotte took part in Belgian theatricals. If anything, she might have been inspired by a school event in Roe Head. Some mad pseudo-scholars says she is being lesbian to Ginevra. I would dispute that. Girls were closer in the 19th century than now, and besides, there is no evidence to prove they are lesbian.
Well, to recap. Lucy refuses the role when M. Paul forces it on her, because she is shy and publicity-averse. He persuades her, however, and when she is on stage she acts well. Before then, she is asked to dress as a man. She refuses the suit, taking only a cravat and minimal items. Some people say she is asserting her feminineness. That is a simplistic view. Lucy is shy, and she feels to dress as a man, she is out of her comfort zone - it is not something a shy Victorian woman would do readily. Cross-dressing wasn't so common then, and it is turning her into a character she isn't comfortable with. Because it is not her nature to wear men's garments, she cannot act herself in comfort.
And yet despite her nervousness she plays the foppish suitor well, according to Dr John. This shows Lucy's insight into flirtatious men - perhaps a touch of William Weightman here? But Lucy's newfound masculinity is not meant to be lesbian or tomboyish - it is a reflection of Charlotte Brontë herself.
When flirting with George Smith she signed off with a man's name, Currer Bell. It gave her the security she could not have as Charlotte Brontë because that would be improper. Well, not really, lots of people wrote flirtatious things those days, and it would have been tolerably accepted among lively flirtatious women, but a quiet soul like Charlotte doing that would be shocking. The world is unkind to souls like her.
But in some respects, Charlotte was masculine in a Victorian sense. Jane Eyre was perceived to have been written by a man, not just because it was course, but because it was vigorous and powerful. Few women have written powerfully before her - even Jane Austen does not come close, with all her subtlety. And (something we hardly credit her for, since most of us think she's feminist) Charlotte was more accepting of men than women in general.
Yes, the little lady who protested against the lack of jobs for women loved men. She might not have had the insight to write proper heroes, but she knew her Mr Helstones, her Mr Donnes and Malones, and her Mr Yorkes. One should never fall in love with one's own hero. When Charlotte was a governess she preferred her male employers to their wives, who she felt were snobbish and viewed her as a slave. The men, she felt, were more intelligent and didn't pick on them. Men couldn't be bothered about these things, whereas women are more personal and therefore more interfering. They gave her a chance to be independent. And Charlotte was not typically feminine. Her method of expression was not common among female writers - passionate, powerful, searing. It was as reckless as a man's. This powerful Romantic style was a masculine thing. For someone who liked bluntness, hated formal society and manners, and loved intellect for its own sake, this is rather masculine. Ladies are more refined in manners and expect more of their fellow-females. Charlotte hated to conform to something she couldn't do. So making her alter-ego Lucy Snowe enact a man well - far more charming than as her normal female self - shows she could have been more comfortable as a man. She also shows she understands the way men are - since she can imitate a flirtatious man so well on stage, and cannot change her feminine character in reality.
As a woman, she is acid to Ginevra, and puts up with her only because she is entertaining and no one else bothers to be nice to her. As a man on stage, she acts out the role of charming suitor far better to Ginevra, the flirt. Curious, but there must be a reason Charlotte put this bit in - it's too obviously dull or insignificant to have been there for no purpose. It could mean Lucy, who conceals herself from the reader, is very reticent about herself, and so has to take up a new role in order to assert her (imaginary) personality. Because she is not dominant or charismatic. And this masculine role shows Lucy's need to adopt a role that isn't her in order to express herself well. An attack on the artificialities of society, perhaps? Lucy can't afford to show her true self to the public because she feels weak and vulnerable. A false front would serve her better. It is more personal than thematic, however, which makes it all the more complicated.
Yet Lucy's masculinity doesn't fit in with her reluctance to dress as a man. Some scholar has come up with the idea that Lucy doesn't want people to see that she is a man, whatever that means. But if I am right, it could mean that because Lucy's character can be mannish, were she to dress as a man people would think at once how mannish she is, that the male garb suits her personality better than a dress - and this she cannot bear. It is more acceptable in society for a woman to be feminine in temperament, not masculine. And it would make her The Other - an outcast who cannot sympathise with her fellow-females. Lucy realises she's different but doesn't want this to stand out, so she conforms to feminine dressing. Notice her dress is a dull dun colour, which keeps her in the shade, unlike her male persona. Perhaps Charlotte thought she would be different if she was a man - respected more, more charismatic, more in the limelight. Certain traits are acceptable in man, shunned in woman. We know this, because Southey wrote to her saying a woman should not make literature her profession.
We see, too, that her meaningful relationships are with men - notable Dr John and M. Paul. There's Paulina, but she is not too feminine in that she doesn't gossip like other women. Ginevra is a diversion rather than a friend. It is the men who respect her as an independent, intelligent woman; Dr John takes her to galleries and concerts, M. Paul discourses with her, M. de Bassompierre thinks she is wise and hopes she will befriend his daughter - they take more trouble with her than the ladies (except Mrs Bretton and Paulina, who are old friends and exceptional women). Even the bookseller who is not even a friend earns more sympathy from her.
After the play is over she is strangely more confident in speaking to Dr John. I suppose the success of the performance exulted her to be more vocal. As a demure shy woman she cannot tease him about his love for Ginevra. In another personality, that of a man, it may seem less shocking to her delicate nature. Lucy notes her speaking out is unusual, and Dr John notices it as well. The mask of the stage has permitted Lucy to say what she feels, without showing her true colours.