Some tools you need in your pocket to be decent at SEO:
-Basic concepts of web design and a relationship with a good designer
-Foundation of simple HTML knowledge
-Familiarity with usability concepts
-General idea of how sites are ranked
-Recognition of dynamic issues and a relationship with a good programmer.
-Strong web research skills
-Good writing skills or a relationship with a good copywriter
-Creativity and common sense
You can't train the last one, but none of the above are very difficult for a motivated, relatively intelligent person to pick up.
Soooooo many people we see here and at other fora are so impatient- just give us the answers. I want a step-by-step guide to seo so I can hand it to my typing monkeys and have them go through it. It's not like that!
Yes, you can help a site (particularly a non-competitive arena) by simply doing keyword research (which may or may not result in the best phrases for the site) and writing new titles, slapping the keyword phrases on the page, and submitting the site to 50 directories. And that is more than a lot of people actually do... and charge a small fortune for!
If you aren't creative and fairly savvy, you may not impact a site in a competitive market much, except for moving them from page 112 to page 86. Boy, they will be impressed...
But if you are smart enough to optimize for both competitive and non-competitive (alternate) phrases, create features that make a site bookmarkable and able to get natural links with ease, and find link that will send tons of qualified traffic (think, coupon sites or specials) you can actually impact their business
as well as their rankings and be worth far more than what they paid you. (The nice thing is that translates into word-of-mouth referrals...
If I were going to set up a training course for SEO's, I'd start by having them build their own site from the ground up. I'd have half of them code a "clean" site and the other half using every trick in the book. I'd have them all compete for the same silly no-competition phrase so that they could see for themselves what really works and what doesn't- with all sites having the same entry date, same tools at the student's disposal, and all things being generally equal.
Then I'd have some "mystery shoppers" search for and purchase from the sites to demonstrate that what may work for search, doesn't always work for people. Usability does count when it comes to making the sale, as does marketing savvy.
The real way to learn is by doing! You can't call yourself an SEO (IMO) if you've never optimzed a site and seen results from it.