That is an interesting idea. After reading your account of how difficult the residents and attendings pimp you and all the reading you did, it does sound like an experience that would push even the best of students. The 4th year students at Barry just finished putting together a packet of reviews on their externship experiences and what they feel are "essential" journal articles; I'm excited to see if any of them went to PSL and what they thought of it.
I may have to look into externing there next year if I can just for a real challenge. Right now, I'm planning to do all of my programs in Mich/OH/PA because that will minimize travel expense and that is where I see myself as a resident and practitioner. Still, it's never bad to try out a top program.
Do you feel that it might be a risk to spend a month externing at a program I'm not truly interested in, though? Or was the experience so good that you feel it greatly improved your performance and ability to answer pimping at your other externships?
...We only go on 5-6 externships (depending if we take a month off or not. I may want to be sure I get a good look at as many of my top choices as possible and that they get an impression of my capabilities before match.