SEO Lesson - Optimize every page for a different keyword phrase

Since search engines rank each individual web page based on its own merit, this creates an opportunity for a web site's sub-pages to rank well in the search results. We all know from experience, however, most search engines will only show 1 or 2 pages from the same site for any particular search query. It doesn't make sense to optimize every page on your site for the same keyword phrase, because those pages would be competing with each other for rankings. This leads us to one of the most significant SEO lessons that I learned:

Optimize each and every page of a web site for a different keyword phrase.

By taking advantage of this lesson, most web sites would easily double their traffic very quickly. The reason is that for any topic, people are using many different search phrases. Sometimes hundreds of different phrases, sometimes thousands. If you focus on a single keyword phrase (such as 'seinfeld'), you are probably missing out on a lot of traffic (examples to follow later).