Chuck points out that abstracting the Developer's work too far away from the system in question means the Developer doesn't really understand the system as a whole. Jeff refers to "purely development roles" and other "pure" roles that aren't necessarily natural boundaries.
The example of VHDL is not about hardware and software, but about learning that you didn't actually know something you thought you knew.
The repairmen in Brazil do not realize (or necessarily care) what they don't know about duct repair. The system allows them to function and even thrive, despite this false confidence in their understanding.
At one point at least, Google was investing in (metaphorically) having DeNiro cross-train those guys, instead of umm... Well, the rest of the movie.
