That is how you should be going. But a lot of webmasters do it in a gradual manner. Practically that will help them use trial and error method. Unless you are a very big firm and have a very strong advertising budget, you will have no idea which direction your website is going to take. At that point, you will need a lot of course correction. Pre planned SEO tactics will need to be rewritten.
When we consider that, a slow start is more optimal for most small and medium business web projects.