I will grant that it is important to mention what you are talking about. I have seen commercials on TV that have made such indirect references to the products they are selling that by the end of the commercial, I still have no idea what they were promoting.

I am a little skeptical about just how big a role peppering an article with the relevant keywords really makes in getting the search engines to spot you. The reality is that if you were to try to select a reasonably popular keyword that is commonly searched for, there are likely to be at least a million websites already using those keywords , and your chances of coming up within the top ten to be even seen by anyone is not high, unless people are looking for such a specific string of words that only your particular website or article shows up.

My other objection is that over-focusing on keywords makes articles very difficult to read, and write. It reminds me of my school days when well-meaning but slightly misguided teachers used to advise us to use many sayings and proverbs in our essays to show our good command of the language and so score higher marks. This sometimes resulted in sentences like "He was in two minds about quitting his job. He was worried that the grass is always greener on the other side, and felt that a bird in the hand is worth two in the bush. He was also mindful that a rolling stone gathers no moss."

You get the idea. I think it is so much more important to just focus on writing a good article and trying to connect with your readers. Afterall, the potential buyers of your products are going to be real people, not search engines.

Now one thing I have found though is that if you write enough decent quality articles about a particular topic and link readers to your websites, the number of links back to your site eventually get you noticed by the search engines anyway. The more articles you submit to as many sites as possible, the faster the process is.

Another advantage of writing articles is that you can provide useful information, presented in the way you want to present it without being restricted by trying to mention a particular word 10 times in a 400 word article. And the more useful your articles are, the more people will want to read more and come to check out your website.

It is after all this, when the search engines have noticed that your site exists, that having a few keywords helps them find you. By then, you do not actually need to keep repeating the word. Just a few times, in the natural flow of writing the article, will do.