IOL is much more about problem solving than you'd think
As a person who is mostly into computers and mathematics, I tended to stay away from biology, linguistics, earth science and some of the other olympiads. I was quite surprised to see the amount of problem solving skills needed to solve IOL problems when I got exposed to some of them.
For example, take this problem,
Given below are English sentences typed in braille (each black circle stands for a raised dot).
Solvers' Choice: Each year, one award goes in the opposite direction: from the contestants to the Program Committee! The Solvers' Choice Award is awarded each year to the authors of the most popular problem, determined by a survey of that year's contestants.