>Go write an auto-pilot system for a 400-seat airliner.......
>
>That's not really a typical software example, though. These days autopilot development is tightly controlled by the airline manufacturers with no competition. Development is done for multiple separate processors by teams using different development platforms in the expectation that different teams using different tools are unlikely to make the same mistakes. I agree that those people would regard themselves as engineers, completely different from your average developer using C# to create a database app.

Agreed it's not typical of what normally gets discussed here (and, I suppose, a fairly extreme example the wider sense). But that doesn't mean that the general principals should not apply to "your average developer using C# to create a database app". Don't get me wrong - I see the benefits of programming in an iterative/organic manner. But that cannot preclude the need for robust (i.e. well-engineered and well tested) code in the final product.