I was wondering the same thing, I would naively have expected that genetic algorithms are absolutely useless for attacking cryptographic functions because the s

I was wondering the same thing, I would naively have expected that genetic algorithms are absolutely useless for attacking cryptographic functions because the search space is full of local extrema. Maybe the used version is really a lot weaker. I would also like to know why the author chose this solution, it would probably have been one of the last things I would have considered. Maybe he observed something that pointed in that direction?