Originally Posted by
Wharbone
It makes perfect sense. If you dress nicer than the interviewer they will feel uncomfortable (you will too). This is a pretty common piece of advice for interviewing.
And about the crystal ball comment, it's not that hard to judge what the interviewer will be wearing if you have studied the job.
When I did interviews I was in a shirt and jeans. Some people came in dressed better than I was. I didnt feel uncomfortable or anything. I mean its not a high profile position or internship...but I think people dressed nice just leave a better first impression. But that isnt even close to being a strong deciding factor.