i agree with eurotrash. getting an interview doesn't mean they lose your numbers and just accept you based on your interview. they look at everything in their decision. so if you were on the lower spectrum of their interviewing candidates numbers-wise, then you'd better have a freakin spectacular interview. you better be able to levitate trinkets on the guy's table with the power of your mind because it's gonna take a miracle. if you're at the top of their candidates numbers-wise, you can have an average interview and still get in. if you have a bad interview, i don't think you'd get in, even if you had good numbers, but it's hard to have a bad interview unless you act like a jerk or something.
example: look at our Lady in Red. she got an interview at UCSF, an awesome school, one that she probably would not have expected to interview at. they interviewed her because she WAS qualified, but she was probably at the lower spectrum of their interviewed candidates numbers-wise. she made up for that with other stuff, and that's why she got the interview, but still, she was probably at the lower spectrum. if i recall correctly her interview lasted damn near 3 hours at UCSF.
u wonder why?? because the dude needed that amount of time to make sure she was right for the school. it took that long to talk everything through, and give the interviewer the feeling that YES, she really would do well there, despite coming up a bit short in some areas. so she must have relayed every right thing at that interview! my guess is she communicated all of her inner strength and will power, and everythign else that makes her special at that interview. so there it is. that's how it works. why? because it 'make sense like a mugg.' so yes, interviews matter a lot, but they're only part of a big picture.
this works out by just thinking logically, i didn't ask any adcoms or anything. but it's logical.