In 2011 I wrote a hub about something I had loved doing as a younger man. At the time another writer had written a similar hub. We commented more than once on each others posts. This helped me decide to go back and edit.
It is a subject I know well and the information has great value to the readers. What I found though was the presentation wasn't as good as it could have been.
This article was set to go to a sub group of keywords (40,000) competition. Surprisingly it has held a page one slot people are finding sometimes to the main keywords and against millions of competition.
My advice, write about what you know and love. If it makes it to page 4 tweak it, not by adding keywords, by increasing the value of the content.