[mdpopescu]

... there are just 256 values to be learned

This is a very good point and it's the reason why I don't find much value in GAs. There is an inherent conflict between "an algorithm for a specific problem" (which can be optimized to run in a short time - the above problem can be reduced to a lookup in a 256 x 2 bit matrix and thus run in O(1)) and "an algorithm for any problem (in a class)" which, while theoretically capable of finding a solution, is prohibitive in time and/or space.

As far as I can tell, GAs are barely any better than a random walk and thus not useful for any non-trivial problems. I am not yet sure if NNs are in the same category, though I suspect they are.