> Can you admit you were wrong yet?
I never made the claim you're objecting to. The modulo operator minimizes the bias, it doesn't eliminate it. And it's the most efficient way to solve the problem.
My suggestion is that you stop thinking like a lawyer and start thinking like a scientist.
Edit: For instance, if there are 59 kids, the first one has twice as good a chance to win as any of the others, because both 0 % 59 and 59 % 59 are 0. In other words, in the set derived from x % 59, for x in {0, 1, ..., 59}, 0 appears twice, and each other number in the range 0-59 only appears once.