Solvers were placed in a room with pencils, some reference books, and the data to analyze. Each individual puzzle gave a bigram; in puzzle order these spelled out HI TL ER BI OG RA PH ER. One of the books provided to solvers was a Hitler biography by IAN KERSHAW; that is the answer to the puzzle.
Individual puzzle solutions:
2. Jigsaw Puzzle:
The first letters of each answer spell out JOKE TYPE WITH PUNCH LINE BUT I, which clues the bigram ER.
THEY WOULD HAVE BEEN CALLED BETA AND IOTA BY SOCRATES AND HIS FOLLOWERS
5. Split Decisions:
There are two places in the grid, symmetrically opposite from each other, containing the letters EX, where it's impossible to form words. But if you replace EX with OG in both places, the puzzle works, so OG is the bigram.
6. Paint By Numbers:
Each of the theme entries contains PH twice, so PH is the bigram.
These six words themselves form another set of jotto clues. The word they clue is ERBIUM, and so the bigram that can be extracted from this puzzle is ER. (IMBRUE and IMBUER are also possible, but neither of them clues a bigram.)
2006 MIT Mystery Hunt