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.)