I'm a certified trainer with the Girl Scouts and I concentrate training Outdoor sections. I have found even the most experienced Leader, camper or outdoorsperson comes away from the training having learned something. Even if it's just a different recipe, game or song. It's of value to the leader and ultimately the youth. But, typically, they learn much more than that.
I enjoy meeting the women and sharing so much back and forth. Plus, the different trainers have different areas of expertise. I've learned a great deal from those that attend and the other trainers.
All training is worth while. Go for it!