I think a good knack for teaching is more important than anything - including a knowledge of the style itself!!!
If you're really interested and want to know some options for how to go about earning an instructorship under some credible folks without spending a fortune, e-mail me at home. I'll gladly share some avenues with you, and I'll give you some contact numbers for some people who won't steer you wrong. My address is
OdysseyResearch@adelphia.net.
Remember, an instructor's greatest responsibility is not to be the best martial artist on the floor. His greatest responsibility is making his students the best they can be. Good instructors should be judged far less by their own talent, and far more by the quality of their students. Few people, after all would make the case that Angelo Dundee could have whipped Muhammad Ali, but Angelo's the guy who taught Ali how to whip everyone else!!