We're now a couple people removed from OP, but I guess that's just as well, as long as a good exchange is still going.
There's nothing wrong with the whole "I'll tell them if they ask" in theory, but it's been my experience that:
1. people don't often ask directly ("are you gay?").
2. folks feel they can dodge all other questions, since they weren't asked THE question.
So if they went on a weekend getaway to the mountains with their boyfriend (say), and somebody asks "What'd you do this weekend?", they'll answer, "I went to the mountains, and I had a good time." Because that person didn't ASK, right? And if that person asks "Did you go alone?", they might answer "I went with a friend" (which isn't a lie - you ARE friends with your boyfriend, right?) or "I just started dating, so we went together" (which isn't a lie - you just neglected to mention the gender, right?). Actually, right now, if somebody asked "Are you gay?", you might just say "No, I'm not"...saving the rationale "I'm bi" to yourself. And think that you're being totally honest, because nobody's asked you if you're bi.
The issue there is that it becomes a game. You ARE, at this point, deliberately hiding this aspect of your life, even if under the guise of "I was being totally honest with my answers". Which seems to contradict the stance of "I'll tell them if asked".
"Coming out" doesn't mean putting up the rainbow flag in your cubicle, or getting into people's faces about it. It just means being forthcoming about it. I've had co-workers find out I'm gay the day they meet me, and others find out months later. It just depends on how much time we spend together, what sort of things are said when they're around, or (most obviously) if my partner comes in to see me at work.
I think you're missing my point. Say I came out to a friend, and she said "That's OK - you can't help it". That sort of implies "...because if you could, you wouldn't be gay." In short, being gay is some sort of burden that you can't help, so hey, best try to put a happy face on it, right?
Sorry, but that's not the case. If I could switch my sexuality today, I wouldn't. I don't consider my sexuality to be some sort of burden. As rareboy puts it, "It's not a curse - it's a blessing". So if this friend told me "I can't help it", I'd work on making her see that it's something that even if I could "help", I wouldn't.
Lex