If by "passing" you mean having everyone perceive you as being 100% female when you're attempting to present as female then that's something that I doubt that I'll ever achieve. I may have gotten close to it for a few minutes at a time when I was younger but not now! I know personally 3 girls who DO achieve this - one is a pre-op TS who has had some cosmetic surgery and had worked really hard to achieve her desired body shape, the other two are crossdressers who happen to have quite feminine features to begin with and really do know how to use appropriate padding and dress to achieve the desired effect. In my experience, they are very much in the minority.
For me, the goal is to present sufficiently female to survive casual scrutiny. For example, as I walk towards the bus stop I hope that anyone who happens to notice me will think "tall, redhead woman" and move on to think of something else. Standing at the bus stop, I expect that I may get a few quizzacle looks but that, unless they dare also waiting for a bus, most people will have much better things to do than worry about who or what I am. However, I have absolutely no illusions about fooling the little old lady sitting opposite me on the bus - unless she's forgotten her glasses AND is fast asleep!
