You haven't answered the questions.
Originally Posted by Kasparoff
I recently experimented with keyword density and onsite SEO and guess what? Got #2 spot in Google from #12 within next 2 days. The keyword I was optimizing for is going for $2-3 per click in AdWords. Thus, keyword factor on the page is still in place.
What keyword? What page? How isolated was the test? How many links does the page have? What are the anchor texts involved?