There is a deep, bad problem with "if you can't read cues, go fuck yourself".
I'm not fine with there being nothing you can do given unclear cues. The cost of two people who wanted to hug not >hugging is negligible; the cost of someone being unable of social interaction until someone comes to clue them in >is not.
I don't think that's what I was intending to get at. If you can't read the cues about the appropriateness of a particular course of action then it is advisable to wait until you can ask someone more informed for information about how to act in a future similar situation.
But that doesn't mean you have to stand there and not participate. For example, let's say you and I are talking and I'm telling you a story about how something in my immediate environment is causing me to think of something that caused me personal distress in the past. Now for the sake of the example, let's say that you and I have met a couple times but are not close friends. During the interaction I shift my body to close out the rest of the room and increase the intimacy and exclusivity content of the private conversation between the two of us. Perhaps I even visibly deflate while telling the story, shifting my posture convey a decrease in confidence and happiness.
This is a situation where it might be appropriate to give someone a hug. But if you're not comfortable reading the cues at the time to determine if this is that kind of situation then I would advise you NOT to ask me right then. Because even though on the surface it may seem as though I have given all the right signals to convey that I would welcome physical comfort, I have not told you anything about the number of other people in the room, the style of clothing being worn by the conversationalists, the presence or absence of mind-altering substances, the relationship statuses of the conversationalists, etc. There are many other factors that could influence whether or not a hug is appropriate here.
And yes, I recognize that in this situation asking "Can I give you a hug" may work out, depending on how "creepily" you ask (and that's a whole different topic, but body language while asking makes a HUGE difference). But most likely I would find it off-putting and it would increase my desire to removal myself from the situation, because this person has just demonstrated either a lack of understanding or a disregard for the general rules of social interaction in my society.
The thing is, not asking about a hug does not close you off to other alternatives that are much lower risk. For example, you could share a similar story from your personal history. You could voice an offer to listen further if I want to talk more about it. You can ask if I would be more comfortable leaving a situation that I have already indicated is in someway unpleasant to me. And while I recognize that each of those actions could be inappropriate depending on the specifics of a given situation, they are much lower risk. And if you're unsure, defaulting to the lower risk interaction option is generally preferable. Plus, like I said, you can always recount the situation later on LessWrong and ask if in the future given those parameters a hug would have been ok.
One of the lessons highlighted in the thread "Less Wrong NYC: Case Study of a Successful Rationalist Chapter" is Gender ratio matters.
There have recently been a number of articles addressing one social skills issue that might be affecting this, from the perspective of a geeky/sciencefiction community with similar attributes to LessWrong, and I want to link to these, not just so the people potentially causing problems get to read them, but also so everyone else knows the resource is there and has a name for the problem, which may facilitate wider discussion and make it easier for others to know when to point towards the resources those who would benefit by them.
However before I do, in the light of RedRobot's comment in the "Of Gender and Rationality" thread, I'd like to echo a sentiment from one of the articles, that people exhibiting this behaviour may be of any gender and may victimise upon any gender. And so, while it may be correlated with a particular gender, it is the behaviour that should be focused upon, and turning this thread into bashing of one gender (or defensiveness against perceived bashing) would be unhelpful.
Ok, disclaimers out of the way, here are the links:
Some of those raise deeper issues about rape culture and audience as enabler, but the TLDR summary is:
EDITED TO ADD:
Despite the way some of the links are framed as being addressed to creepers, this post is aimed at least as much at the community as a whole, intended to trigger a discussion on how the community should best go about handling such a problem once identified, with the TLDR being "set of restraints to place on someone who is burning the commons", rather that a complete description that guarantees that anyone who doesn't meet it isn't creepy. (Thank you to jsteinhardt for clearly verbalising the misinterpretation - for discussion see his reply to this post)