Good point, Tedster - I publish much of my content on article sites that have ranking juice behind them. Articles on those sites do NOT rank universally well, but there's still stuff happening behind the scenes about which I know nil.
I guess part of the problem in SEO advice being offered blindly is unscrupulous or negligent attitudes, but I honestly think a lot of the bad SEO advice comes from people who feel true enthusiasm about the fact that in a world where the old economy is tanking, there's real opportunity here, and that the important part is giving advice at all.
It's kind of like we're boarding a new ship and the latest of us aren't even sailors. We're like, "Come on board, it's steady sailing here!" The people on the old, sinking ship are like, "But how will I manage there? I've never lived on a vessel that mighty. My boat may be sinking, but at least I know where I'm supposed to bunk down." And we're hollering, "Easy. You walk like this, sleep like this, eat like this, and don't throw yourselves overboard. It's great here." So then they come aboard and fall down and get lost and go hungry and don't know what to do. And we smile at them and say, "Welcome aboard. You're an adventurer now. You'll figure it out." (Or the grumpier of us just grunt, shrug, say, "Go figure it out," and turn away.) Because that's what we're all doing, even the seasoned ones.
I've been earning online for many years but learning SEO for only a fraction of that, so I'm anything but seasoned. Still, I want to share advice, because I think the boat will float better if everyone's a better sailor. But the problem is, specific SEO techniques are obsolete almost by definition the moment they become public. I just tell people they can do it, because for the first time in a long time, your average Jane without money or degrees or a long resume really can. They just need to get out of the paradigm that they're living on the old boat, which had a clear compass guiding success, and into a pioneer mindset.
Anyway, like others here, I believe that the best optimizers are the ones who experimented a lot and learned from it, and that SEO advice is useless without going through that process.
And it's also pretty pointless to offer advice without specifics. I seem to recall Matt Cutts leaving a message on a feedback thread here that he doesn't come to Webmasterworld as much as before because nobody can talk about website specifics. It's kind of like that. SEO advice handed out without knowing the niche, the scale, the goals, and the content is the equivalent of handing out a lifeline - it gets people temporarily back on board, but it doesn't help them sail.