I have a couple pages that have been optimised and were performing well for x3 long tail focus keyphrases. I've been careful to avoid stuffing but all of these keyphrases include the same two words somewhere in their construction.
When I added a new long tail focus keyphrase that includes these two words, I lost several ranking positions upon reindexing. I waited it out for a few weeks but lost my nerve and removed the x3 references to this keyphrase and all was well again.
With the addition of the new focus keyphrase there were 22 uses of a word that's a component of x4 of my focus keywords on a page holding c. 700 words. So even though I'm not trying to rank for that word itself - "safety" in this instance - could 3%+ keyword density relating to a word I don't want to rank for be interpreted as stuffing and impact ranking position?
Any insight would be much appreciated.