I think R/S value is just as worthless as KEI. From what I understand, it's not just one thing that makes for a great keyword/keyprase. You have to look at R/S, KEI, the way your site passes keyprases and what your competition is doing with links and google PR.
It's a combination of these factors that determine your SERP.
look at the top site for the keyprase "search engine optimization" for example. No doubt it's a site thats been around for a while, but look at the meta tags keywords in the index. There's more than 5.
The 5 after that suggest to me that they are there only to give the other squeeze pages weight? That's something I'm currently testing, and I'm not sure this is true.
I've optimized my own website for one keyprase that is getting over 8 million results on MSN. I don't have a lot of great link partners, but I have related keywords in my other pages that make this keyphrase rank well.
I'm still testing using Keyword Elite and SEO elite, and this is my first post (hey all!). Thoughts are welcome.
To answer your question, I think that depends on what you're optimizing for. Are you optimizing for PPC or organic search?
[edited by: 2aminPhoenix at 11:51 am (utc) on Dec. 17, 2006]