Yes, and by not honoring their commitment, the person could be labeled "unprofessional", and they would be, unfortunately correct in that regard. Why? Bc that's the deal you agreed to, if you go there. They won't necessarily say they're bad or incompetent (bc they finished residency after all), but they'll either blackball you in a letter or by phone since every academic derm is friends with every other academic derm. They won't hire you bc they don't want to piss their fellow friend dermie off (the ones they see all the time at AAD and collaborate with). In general, other programs don't get your individual evals during residency. Hiring for a job, esp. in academia, is a lot of time political, based on good word of mouth and holistic review.