It's a little bit of irony that the example of the author points to architects relying on a CAD system, a system that was presumably built by programmers. Who had to understand that the results their software produced had to have a high level of reliability--if it produced a wrong result, buildings could collapse, people could be hurt or killed. Errors would be extremely costly. So it's not impossible, just most software isn't held to that standard, because there's less incentive.