I'm going to go ahead and agree with your preceptor on this one. I've had an interest in otolaryngology and done a whole lot of research on the subject, spoken to the people in the department at my school, and so on.
Otolaryngology is competitive to a stupid degree. Everyone wants to be a surgeon without the awful hours, and everyone is looking for a back door (not to mention a less grueling) path to plastic surgery. The reasons for its competitiveness, as with most competitive fields, are very superficial...making it frustrating to be an applicant with a legitimate interest in, say, head and neck cancer or otology.
The standard scenario is as follows: Top 30 NIH research med school student, 250 Step 1, Honors in Surgery and several other rotations, two or three research projects, one away and great letters....applying to 50 places...gets you...
...11 interviews, in random places throughout the country. You attend 10 of these due to a scheduling conflict...
...You rank 9 because you hated one of them, and you match at #7.
Congratulations.