Interesting topic. I have a habit of biting my nails, so they've always been short. But I don't think nail length is going to help or hinder your ability to pass. My brother has REALLY long nails for a guy. The only kind of comments he's ever gotten were, "Wow, your nails are so long, how do you grow them like that?!" A lot of women envy his long fingernails, lol. IMO, long nails are a sign of healthy nails and hands, not so much a gender indicator.