There is no such thing as a perfectly optimized page. Search engines do not want to return the most optimized page, but the page that best satisfies the searcher’s goals.
If you have a page title and H1 header that are exactly the same, and all of your internal links and all of your inbound links from other sites pointing to that page use that same text, then that looks suspicious (like attempted ranking manipulation). As a result, the search engines may de-weight that or filter that out of the search results.
How do you minimize your risks and make your site more stable? It’s best to mix things up a bit and create something that markets itself. Or, try looking at things like a search engine engineer would.
There is a concept called poison words, where if you have things like link exchange, add URL, or link partners on a page, there stands a good chance a search engines may place less weight on that page or its outbound links. In the past, some common poison words were things like forum and guestbook. The more likely the content is to be of low quality or related to spam, the more likely search engines want to de-weight it.
Search engines may want to penalize the use of “spammy” sites using an H1 header, so instead people use an H2 header for the highest level header tag on the spammy sites. Maybe they look to de-weight site-wide links to the home page near the end of the page code using the exact same link text as the home page’s page title, so instead you link to the home page from earlier in the page code and/or use slightly different anchor text than your page title and most of your link profile.
Keep in mind that some of the search relevancy algorithms are genetic algorithms that train themselves to test the relevancy of new result sets, but humans still program them. Google wants to have a bias toward informational resources. Yahoo! will be more biased toward commerce. These biases can affect optimization, as well.
In addition, some guys like DaveN mention lots of subtle tips like the ones we just discussed. If you think like a search engineer, those techniques that are common in SEO and not so common on regular websites are the most likely to be de-weighted or penalized. Remember that optimizing content is about matching quality signs, but if you match too many too closely, it could send a negative signal.
Now we hope that you know some common SEO techniques which can help in more visibility of your site.