You can make a lot of money detailing, but you need to start now. There are things that you just aren't going to learn in a classroom. I guarantee you that half of what you learn there is either going to be stuff you already knew or aren't going to apply every day. Half of what is left is very valuable and worth the trip. Whatever is left is stuff you would have learned by doing anyway. So it is up to you. I'm definitely not dogging taking the class. I think it would be great. In fact, my ambition in life is to teach those types of classes. I just don't think that you need to wait to take them before you start working.
What is your degree in? Is it going to help you in detailing at all? I'm just curious. I've got degrees that are certianly not detailing related too and am always curious to know what brings others like me into this industry.