I understand what you are saying, but just because you have alot of experience diving doesn't mean you are competent enough to be an instructor. Working in a PADI 5 star I have had plenty of experiences with incompetent instructors that have alot of diving experience and seeing new DM's who are much more capable and also have a better understanding of diving.... Being an intern you get the experience and knowledge of real life dive situations that he will have to use as an instructor sence he will be hands on. I guess it all comes down to the person and how much they can get out of what ever experiences they have.