Yeah... good answer. I *think* it's great, too. I hope so, for your sake.
Basically, if you look at the schedule for class of 2009, there's no time in it to study for summative exams. The administration figured if they weren't giving us adequate time to study, there's really no point in giving the exams.
It wasn't really a big deal for anatomy, since it has its own summative which is combined with testing new material. So it was just like a regular final. But the 3rd summative tested fuel metabolism (aka biochem), immunology, and microbiology. That's 11 or 12 weeks of material, and we had 1 whole free day to study (and that was only because they made the summative on a Saturday).
So basically, it was pretty stressful and I guess they didn't feel like they were achieving the goal of having us relearn the material if all we were doing was cramming for a day or two.