Interviewing as a rotator

You should only rotate at places where you feel like you have a shot at matching if you impress people over the course of your rotation. Otherwise, you're really wasting a great opportunity for yourself. At the end of your rotation, you should have worked so hard and so well, that the thought of not getting an interview should not even enter your mind. Personally, I would not even broach the subject of a courtesy interview with the program director -- you have to put yourself in a position where it's not a courtesy, but rather a guarantee.