SEO from a writing standpoint has become rather easy. It boils down to picking a keyword phrase and using that phrase in your meta title, title and the first paragraph of your article. After that, the best SEO is not to worry about it. Google is cracking down on keyword stuffing and 'overly optimized' articles, but the number one SEO tip -- writing great quality content -- remains the same.
He is 100% correct....search engine optimization largely boils down to not stuffing ANY words and writing top quality content. What few writers fail to realize that many of the main SEO traits tracked by Google since the Panda update are things like average visitor time, article readability, and several other visitor-friendly metrics.
If you're given a keyword/phrase from an employer, use it naturally in the text 3-4 times per 500 words (preferably starting in the very 1st sentence), find a relevant photo or two that can be labeled with that keyword/keyphrase in the alternate text, quote your sources (preferably using the keyword in the anchor text), and just write great articles that people will find value in.
For example, if I were to write about Disney World, I'm not going to tell people it's in Orlando and it encompasses 2,700 acres with 142 rides (which is what most info-type articles say)...I'm going to tell my readers about the best rides, the most interactive areas for kids, the best times to visit, where to get the best food, and stuff like that from an authority standpoint. Knowing your subject is what separates an average writer from a great one and that's the main factor of SEO.
Hopefully that helped.