Re: Hot water heater tech.
Off the top of my head, I can think of two ways computers in aerospace engineering have some negatives.
First, when making revisions is very easy, it becomes very tempting. "Good enough" never is. Come to think of it, that applies to word processors and writing, too.
Second, there can be too much reliance on computers and not enough on real-world testing. When it comes down to it, there should still be room for wind tunnels and flight test programs in a good development.