I think you're being a bit dishonest here, calling responses 'evasions' when they're clearly not. You asked a question (What is she doing wrong?); I gave an answer (She's being antisocial.) Maybe it's an unsatisfactory answer, but it's not an evasion.
I still think it's an evasion, because "antisocial" is really just another way of saying "wrong."
Society generally functions better when people work together and exhibit altruistic behaviour towards one another.
Society also functions better when people exercise caution. If everyone is trusting, then it's very easy (and therefore rewarding) to exploit others, so exploiters prosper.
Walking around predicating your interactions with every second person you meet with "What could this person do to harm me?" is in opposition to societal benefit. Obviously, it's a sliding scale based on the conditions and environment.
I question whether a good society is one where everyone is continuously thinking "That person could rape me. That person could rape me." Yes, I know that the most efficient way to deal with the problem is to get rid of the rapists. Note that this is being addressed in society, but isn't going to be accomplished by pessimistic speculation on what people could do, only by dealing with what they've actually done, or are likely to do.
But what's missing from your explanation is an identification of how this woman's personal assessment of risk and benefit affects anyone else. When I'm walking down the street, I don't know if the woman in front of me thinks like the author does, or like you do. I have no way of knowing. Either way, to paraphrase Jefferson, it neither picks my pocket nor breaks my leg. I don't believe in "bad vibes" or "negative energy" from another person's mere thoughts, and I trust you don't either.
What I'm waiting for you or anyone else to provide is a link between the thoughts and attitudes to which you object, and behavior that you claim has negative consequences. All this stuff about "societal benefit" is hopelessly vague. If your argument is "women should be pleasant and friendly when a stranger starts talking to them on a train. Continuing to read your book or asking to be left alone is rude," well, I would disagree with that, but at least I'd know where you were coming from. But as it is I have no idea what negative or antisocial behavior you think this incorrect attitude is causing.
Granted, it is much less likely that I, personally, will be raped than any given women, but it's possible. Should men also not talk to me in case I think they're rapists? Is the probability that I will be raped low enough to ignore? How does one objectively determine the acceptability of probability?
It's up to each person to decide what risks they're prepared to run. As to whether men should or shouldn't talk to you, bear in mind that the author was simply giving advice, not issuing orders. Her point was that, if you want to get a positive reaction from a woman, you should bear these considerations in mind. Of course, implicit in that advice is the claim that many women think as she does. If that's not correct, then I suppose one can disregard the advice as not being very applicable, just as I would disregard advice that said "never wear a blue shirt on a date; most women hate blue," because I'm pretty sure the claim is false and that while this particular women hates blue, she's not representative.
So, to answer your question, if most -- or even a significant number of -- men are concerned enough about rape to be uncomfortable with being approached in a particular situation or manner, then yes, the polite and prudent thing to do would be to avoid making such approaches. As I don't believe that to be the case -- and I don't think you would claim otherwise -- the advice is less applicable. (Much of it is still somewhat applicable: if you want a positive social interaction, you should be aware of the cues people are giving off and respect what it means. If I'm sitting beside you on an airplane, and I've got headphones on and am watching a movie or working on my laptop, it's really not a good time to try making small talk with me.)
Her words:
You want to say Hi to the cute girl on the subway. How will she react? Fortunately, I can tell you with some certainty, because she’s already sending messages to you. Looking out the window, reading a book, working on a computer, arms folded across chest, body away from you = do not disturb. So, y’know, don’t disturb her. Really. Even to say that you like her hair, shoes, or book. A compliment is not always a reason for women to smile and say thank you. You are a threat, remember? You are Schrödinger’s Rapist.
i) Some men are rapists.
ii) Rapists are threats.
Therefore, all men are threats.
Fallacious. Men are threats simply for wanting to say 'hi' to a girl on the subway? Certainly a man shouldn't be labeled as a 'threat' just for wanting to say 'hi'.
I think you're misreading the quoted excerpt. I think it's pretty obvious from the context that the author is telling the reader that,
from the perspective of the girl on the subway, he is a threat.
Maybe she's not sending signals, maybe she hasn't even noticed the guy. The women is not obligated to respond in any way whatsoever. She could ignore him, or say a polite "Thanks." and go back to reading, or, if social conventions aren't important to her, say, "Piss off, you maggot." Is the author suggesting we never talk to anyone unless we already have their complete, undivided attention? It certainly sounds that way.
Come on, surely you don't think that's what the author is suggesting. Geez, she even bolded the key points for you: "accept that I set my own risk tolerance," "be aware of what signals you are sending by your appearance and the environment," "Learn to understand and respect women’s communication to you," and -- most applicable to your question -- "If you fail to respect what women say, you label yourself a problem."
So sure, you can chat up whoever you want, whenever you want. But just as you note above, there are social conventions. Saying "piss off, you maggot" is considered rude (unless there's considerable provocation, I suppose). "Don't disturb people who are making it clear that they don't want to be disturbed" is another social convention -- or, if it isn't, the author is arguing that it should be. If you missed those signals, well, mistakes happen, and some people are more perceptive than others (and some people's signals are less clear than others). And, like most social conventions, the only punishment or enforcement is that people will change how they think of you and how they act. You're free to dispute that this is or should be a social convention, but again, that has consequences if you're wrong.
If not, where's the line? How do we logically determine it? Or is she just asserting her opinion as fact?
I'm lost -- are you asking how we logically determine when someone is willing to be approached by a stranger? I'm not sure it's a matter of "logic," just of empathy and receptiveness to social cues.