Hi,
I don't know the exact working of this method, but to me seems to b a
great way to conduct test.
The problems were all hard, between M40 to M50 level of difficulty
[1],
if you use Knuth's terminology. Part of the skill was to avoid wasting
too much time on the M50 (open/unsolved) problems, and to focus on
solving at least 1 or 2 M40 problems. An average student could
definitely
have solved at least one in 3 weeks with just a few hours at the
library. And getting just 1 correct would have got a B grade, and 2
would
have got an A grade. One could even submit a blank answer sheet, get
0/30, and hope for a C or D. But given the ingrained cultural mindset
in
most of us to take shortcuts to get ahead, many did cheat and were
discovered - netting them a straight F and 3 wasted credits.