Edwin is 100 % right. That was the whole purpose of LSI being implimented. to stop the keyword stuffing wars with marketers and to make a wedpage more natural for the surfer.
Write for the visitor and you will be ok, make sure your titles are on target and get some quality links.
Remember, 20 % onpage and 80% links. So, if this is the general rule, what small percentage could density account for anyway? We know that the title carries the most weight with onpage, then h tags, so how much could keyword density count for?
The fact of the matter is that you can have all of your onpage wrong and still get top placements with proper anchor text and quality link. I know i sound like a broken record with this, but "click here" in not on the adobe site anywhere and it ranks # 1 for it in Google.
G.W.Bush used to rank # 1 for "miserable failure" and many claim that Google stopped this but the fact is that the whitehouse changed the filename of G.W.'s profile page.
This was the origional URL to the bio that ranked for "miserable failure"
https://www.whitehouse.gov/president/gwbbio.html
Now his bio is located on this page.
President of the United States - George W. Bush
Remember, 80 % links.