A lesson like this will help on how to set up a practice routine that will work for you. Something that doesn't always comes up during my live lessons with my own teachers. They provide the lesson, information and how you do it is entirely up to you.
So yes, if you practice in the wrong way - it will take a week before it's noticed. If, however, you learn how to practice proper I'm convinced the time you need to study on songs will be a lot less.
