You post seems to be insinuating that we deem GAs as a panacea. No one here is saying that; to the contrary, we're just trying to see how we could use them for dynamically generating interesting test-input data. In addition to that, I'm just thinking out loud if you could possibly append to that functionality and see how to "prepare" more interesting test cases when multiple layers are involved.

No one is disputing the fact that you need an expert to tune these to get the desirable result for hard problems. I argue that having a "good enough" understanding of GAs (i.e. you don't need a PhD in the subject) should be sufficient for you to solve simpler problems such as the one we're discussing.

Do you have any counter-arguments to that? Can you cite any other examples where this view is challenged?