This is excellent advice, and I up-voted it. However:
If she seems annoyed or condescending or whatever, try to shrug it off; just smile and say "okay, no problem" or something along those lines. Do the same thing if she says "I'd rather just be friends." (But for the love of Pete, do not spend a lot of effort trying to actually cultivate a friendship. Moooooove on.)
I may just be reading too much into things, and I acknowledge that this comment is written primarily as a response to the question "how to get into a relationship". Nevertheless, this bit bothers me a bit, as the "for the love of, don't try to actually cultivate a friendship" part seems to imply that there's no point in being friends with women if you're not going to have a relationship with them. That strikes me as a bit offensive.
Even if we're assuming that you're purpose is solely to get women, I don't think befriending lots of them is as useless as you seem to suggest. You say yourself that one's friends may introduce one to somebody one might be interested in. People tend to have more same-sex friends than opposite-sex friends, so being friends with lots of women will increase your chances of one of them introducing you to a friend of theirs. I also suspect that women are more likely than men to do this.
I do admit that this may not be the most efficient approach if you're optimizing purely for finding a romantic relationship in minimum time. But on the other hand, it can wield you rewarding friendships that persist long after the end of your relationship with whoever it was you eventually found, so personally I'd find it worth it.
I should also mention that my experience somewhat mirrors MBlume's, and I find the notion of becoming involved with someone before being good friends with them a little off-putting. Which is not to say that it would never have happened to me, though. (Without going to details, suffice to say that I've both had relationships with women I was friends with from before, and with women where that wasn't the case.)
I believe the point is that if you want a romantic relationship with a woman, cultivating a friendship with her in the hopes that romance will develop is almost always a bad idea. Occasionally such romance sparks "out of the blue", but more likely nothing will ever happen, and it is a huge investment of time and emotion that basically never pays off. So if you aren't interested in the woman for the sake of friendship alone, it is better to just forget about her and move on.
If you find a person interesting and worth being friends with, by all means don't reject such an opportunity just because the person is a woman. That's idiotic. It's just a terrible dating strategy, that's all.
I am beginning to suspect that it is surprisingly common for intelligent, competent adults to somehow make it through the world for a few decades while missing some ordinary skill, like mailing a physical letter, folding a fitted sheet, depositing a check, or reading a bus schedule. Since these tasks are often presented atomically - or, worse, embedded implicitly into other instructions - and it is often possible to get around the need for them, this ignorance is not self-correcting. One can Google "how to deposit a check" and similar phrases, but the sorts of instructions that crop up are often misleading, rely on entangled and potentially similarly-deficient knowledge to be understandable, or are not so much instructions as they are tips and tricks and warnings for people who already know the basic procedure. Asking other people is more effective because they can respond to requests for clarification (and physically pointing at stuff is useful too), but embarrassing, since lacking these skills as an adult is stigmatized. (They are rarely even considered skills by people who have had them for a while.)
This seems like a bad situation. And - if I am correct and gaps like these are common - then it is something of a collective action problem to handle gap-filling without undue social drama. Supposedly, we're good at collective action problems, us rationalists, right? So I propose a thread for the purpose here, with the stipulation that all replies to gap announcements are to be constructive attempts at conveying the relevant procedural knowledge. No asking "how did you manage to be X years old without knowing that?" - if the gap-haver wishes to volunteer the information, that is fine, but asking is to be considered poor form.
(And yes, I have one. It's this: how in the world do people go about the supposedly atomic action of investing in the stock market? Here I am, sitting at my computer, and suppose I want a share of Apple - there isn't a button that says "Buy Our Stock" on their website. There goes my one idea. Where do I go and what do I do there?)