One exam for the entire semester in an effort to simulate NDBE? That's insane and runs counter to the NDBE in the first place. The exam was created as an overall, equalized assessment of every US dental student's knowledge after their first two years and final two years in dental school. By mimicking the NDBE's format in rarely testing, NYU has basically forfeited their ability to prepare students for the exam in an efficient manner. Student success on the NDBE comes through long term preparation and repetition of subject material. Instead of actually judging each student's progression over time and giving each student an opportunity to make up for a marginal grade through subsequent testing phases, it appears the administrators have other ideas in mind.
It is understandable why the previous class rejected the idea. Not only is it a disservice to the students, it also facilitates complacency among staff and students. With such a huge block of time between testing, a student cannot judge his/her own abilities within the system but once. I think if you ask most students, they would tell you that they don't mind being tested in shorter intervals. It allows for much easier dissection of the topics and gives an instructor a better picture of the coursework progression and room for adjustments should they be necessary.
This is without question material suited for guinea pigs. The professors only have to give one exam for the entire year. It's a fine example set forth to the rest of the student body that is trying to follow in their footsteps to become professionals. Just check your students' progress like you check your patients' teeth every checkup. Actually, lets don't even do it that frequent. Lets check the students once a semester and pass/fail them. That makes perfect sense.