I was pleaed to see this subject arise. In our dojo we strongly promote bunkai. there are 2 different types. formal and informal. this is a wonderful learning tool for both the student and instructor. I think this is where, once you are a upper rank, you put your own spin on things. Not changing the traditional way, but putting a little spice and zip into your own style. I think you honestly cover all of the basics and then some with practice of bunkai.