Yes, this is similar to the first point; however, it's important to take this one step further. Don't just stop at “best sleeping bags” or “sleeping bag reviews”! You should target phrases that are even longer tailed, which could mean going after keywords with very low search volume. I do that here on Niche Pursuits and every blog or website I've built.
Affiliate marketing overlaps with other Internet marketing methods to some degree, because affiliates often use regular advertising methods. Those methods include organic search engine optimization (SEO), paid search engine marketing (PPC – Pay Per Click), e-mail marketing, content marketing, and (in some sense) display advertising. On the other hand, affiliates sometimes use less orthodox techniques, such as publishing reviews of products or services offered by a partner.