SEO techniques

[jabo]

Well, this thread is not to discuss the different SEO techniques that people use for their websites but I just had some question about those techniques and the websites that SEO people use it at.

I have been in different forums for quite a while now and still I have seen a lot of comments saying that a certain SEO technique is a waste of time but some people say that it is not. So my first question would be, how did you choose to do the SEO techniques that you are doing now. For example, you do article submission instead of directory submission, why is that so? is it because somebody posted it in a forum or a blog that the other technique is a waste of time or did you came to find out about it yourself?

Aside from the different comments on the techniques about SEO, there are also differences with the different results that specific websites can give. Say Digg and Stumbleupon.. and like the first observation, some people find success in the other and failure in another. (although both can be failure and success at the same time). and as same as the first question, just wanted to know how you chose sites like this to participate in at.

Do you do experiments for these websites and these SEO techniques? Do you seek to advice and suggestions given by different blogs or forums? Do you follow what most people do?