You might be right in that it technically is the best approach, but pedagogically the value of starting with a more specific jQuery, or Rails book is that it's

You might be right in that it technically is the best approach, but pedagogically the value of starting with a more specific jQuery, or Rails book is that it's just more fun to build something that immediately does something that you can see and play around with, especially if you can do so right within the browser. Of course, it's not a good thing to stop there, but in my experience it often acts as a gateway for beginners to start actually learning 'proper' programming. My brother, for example, has been working through the Rails tutorial, and already he's starting to read more general ruby books, doing javascript tutorials, and thinking about building a game for the browser using Rails as a backend. Plus, he'll be able to make money much sooner this way, which is a great incentive for him to keep at it.