This is a difficult question to ever get a straight answer on. There certainly is talk among program directors... no doubt. I would think that the Gen Surg people would be more offended then the Ortho people with dual applying (since they know your first choice will be ortho). Most of the time the concern I hear from the faculty is that applicants are overconfident, not the other way around. I am sure there are some ortho departments that would interperet applying to a backup as "you don't want ortho bad enough", but I think this would be the minority. The other choice would be to apply to a few programs at places that you aren't interested in doing ortho and don't overlap your apps.