James,
There is much more to starting your own detailing business than just learning about detailing and how to market a detailing business.
What about many of the other steps necessary to successfully start-up, own and operate your own professional detailing business, such as; 1- writing your own business plan, 2- establishing your own advertising strategy, 3- finding ways to get free publicity for your new business, 4- identifying what detailing supplies and professional products you will need in order to get started, 5- identifying what detailing services you will want to offer your customers, 6- establishing your own quality assurance inspection process, 7- creating ways to measure whether or not you are meeting your own business objectives and goals.
In summary, I believe that professional detailers need to concentrate on business principles even more than they concentrate on detailing principles. I would say that 80 percent of the educational effort should be focused on learning more about what it takes to own and operate a successful and profitable business. The other 20 percent should be learning more about the actual process of detailing.