Sometimes people build sites without considering SEO. While this is typically what webmasters who don't know about SEO do, it's not the best way to get things done because the site will need to be modified heavily. A Cre8asite Forums member did this and now has to start over: first, he registered his site with Google Webmaster Tools, and then he did some updates to the copy. What's next?
Well, yes, while this is definitely the reverse approach, it can still be salvaged, but a lot of changes will need to be made. Don't forget unique titles (which should be done earlier than later!). Add some good copy to your site. Add descriptive anchor text for links. When it comes to identifying keyword strategy, you now need to brainstorm what keywords to target. SEO should really be part of the development phase before anything else.
The important thing to take away is that the visitors come first. The site needs to be designed for them, and then you should worry about Google. When it comes to a site redesign, you should really prepare your SEO strategy properly and give the customer power to make changes.
Forum discussion continues at Cre8asite Forums.