Yeah, probably we CAN all just get along.
Can one read Tom without some bemusement at the base assumption -- that whenever two guys who are strangers start a conversation, there's a chance it will lead to ass-fucking?
Not to say you've got it wrong, Tom (may I call you Tom?). It's a thoughtful, dare I say sensitive essay. You didn't invent the straight sign, you just noticed it; kudos for living consciously.
But isn't it a sad custom, really? Are we grown so alienated as all that?
As an erstwhile bisexual and longtime socialist --um, socialite --um, social person, I have been both signer and signee. And here's the thing: it doesn't happen much in line at the Kwik-E-Mart. I can think of two messages that have to be shared both ways:
(a) We have a common sense of place (same bar, same town, etc.), or interest (NFL team, political party).
(2) Your perspective on (a) is potentially valuable, or at least interesting, to me.
Is there anything more essential to the craft of flirting than that? (Eventually there's hand-touching and stuff, but that's usually a bit farther along.) Any reinforcements of the above messages lead in the direction of "The Straight Sign". Perhaps some enterprising grad student could devise a rubric (the more specific agreements in perspective, the fewer reinforcements?).
What we're really talking about is a more general "boundary statement", as Tom recognizes by noting "the Boyfriend Reference"; the boundary statement says, "Sex is right out". That's cool, and I think worthwhile. Let's just recognize that "I'm not putting the moves on you" isn't the same statement as "Dude, I'm straight". I've set the boundary in a couple conversations with a Boyfriend Reference.
The sad truth of the Straight Sign is that it can slam the closet door. A guy who's not fully out can duck into exchanging a "straight sign" just because he's not on the hunt, but doesn't want to risk misunderstanding or spend an awkward eternity discussing orientation issues. If I have to come out to every guy I want to argue politics with, I'll bore myself to tears and then some.
Anyhow I'm a grown-up, dammit. That means I can talk to strangers. I don't talk to strangers exclusively for the purpose of gettin' some action; I do it because I'm a social animal. We have to engage one another every now and then, or we lose a bit of our humanity. Guys who don't see that may have some trouble starting conversations with women, without knowing why.