Learning curve
You will never stop learning when it comes to showing dogs (or anything else!) but is there such a thing as learning too much? I don’t think so.
Talking about purely show ring training/ handling, you can never learn too much. Try to go on as many workshops as you can with different trainers. Each trainer will have different handling and training styles and each day your dog may perform differently, as well as many other factors.
Be careful though as you may get conflicting advise. This is where you need to use these different styles to find the one that best suits you and your dog and to develop your own style of showing.
If you find a trainer you like and enjoy their sessions, go on the same one a year or two later. You might pick up on something you missed previously.
Enjoy the training sessions as use them to your advantage.
Happy training!