More keywords Ranked: Longtail or Shady SEO?

I am a firm believer in Chris Andersons’ Long Tail. This is where the revenue from small margin items produce the bulk a company’s revenue by sheer number of such small items. In the SEO world, this translastes to having a client’s website optimized not only for a couple of phrases, but optimized for as many keyword phrases AS IS RELEVANT for the page.

The belief here is that each additional keyword phrase may bring in additional visitors. And if you add all these small increments, the result is a webpage that has a significantly more traffic!

However, since some SEO practitioners are charging based on the number of keyword phrases that they can rank a webpage on, there is a point at which the client’s best interests are subverted in favor of the SEO practitioners’ best interest. What is to stop the SEO from just adding keyword phrases, that although ‘related’ to the webpage, may not actually be pulling in traffic?

For example, if your client is selling cookies. Then relevant keyword phrases might include “selling cookies”, “chocolate cookies”…but would there really be searches for “selling 1960 style cookies”? and then you see a bunch of “Selling 1961..”, “Selling 1962…” and so forth?

Is the interest of the client being served? I think this is [tag-tec]shady seo[/tag-tec].