Yep, there are some schools out there that may take all of their own students or only people that have rotated there, but in a way that is kind of expected and natural. For alot of these places they are dealing with known quantities as opposed to 500 unknown pieces of paper that they have to choose from. I don't blame them, especially when they like somebody and they know that that somebody wants to come there.
We have AI's rotating here (UF-Gainesville) all of the time, there have been some people that have come through have really impressed us and believe me have been ranked high enough to match. There have also been some people that we have found out were real stinkbombs and were glad to have seen their true colors.
Last year if I am correct, most of our top five ranked, were either students here or rotated here, regardless of that we matched one UF med student, one guy who rotated here and one gal who didn't. The number of applications ARE going up (at least they have here) and every applicant has awesome CV's, rec letters, research projects, etc. It is just one more way to find the individual that best fits in with the residents, the faculty, the work ethic and expectations of the program. It's that unkown and unmeasureable quantity or feeling that you are able to get about someone that I think residency programs are trying to get a sense of. Hopefully, in encouraging AI's, the students see the program and the programs don't get stuck with a stinkbomb.
DO an AI if you possibly can, I did 2 as a fourth year. It opened my eyes immensely as to what else is out there, both good and bad. IF you like a place or think that you may be on the cusp of being competitive at a certain place, rotate there, it is well worth it, and usually helps tremendously come rank list time.
