When it comes down to it you're looking at the difference between 14 or 28 words in a 700 word article - sure, following the Panda update this COULD result in what many people feel is "over-optimization" but really, so long as the readability remains strong and the audience is engaged, it doesn't matter too much.
As an example: You may mention SEO or other related terms a LOT in an SEO-targeted article and run way over even a 4% keyword target. So long as the article is good, though, it'll add value to the website and be worth the overall time (and cost) associated with it.