NRMP policy is that programs cannot require a second look.
http://www.nrmp.org/code-of-conduct/
There is a
huge variance by region on the issue of second looks. If all of a program's candidates are in driving distance, so what, but when candidates have to pay additional hundreds or thousands in travel expenses
again and take time off from clinical training
again that's ridiculous and irresponsible. The NRMP and ACGME are clear in their disapproval of programs that use second looks as part of their candidate review processes.
I might
ask for a second look when I can't make it to the resident dinner and am not otherwise able to form an opinion on the current residents at one of my top program choices. I don't expect a 2nd look to do anything tangible to my chances at a program.
This is completely different from the med school admissions process where you're holding an acceptance as you're making a decision, and a second look is on top of a
sure thing.
I suggest that if there's no further information that you need from a program after interviewing, and you love the program, that you should then consider asking your department chair (with maximum polite professionalism) to make a phone call on your behalf instead of using time and money to go visit again.