> who, today, can write or optimize assembly by hand? How about understand the OS internals? How about write a compiler? How about write a library for their fav language? How about actually troubleshoot a misbehaving *nix process?

But developers should understand what assembly is and what a compiler does. Writing a library for a language you know should be a common development task. How else are you going to reuse a chunk of code needed for multiple projects?

Certainly also need to have a basic understanding of unix processes to be a competent developer, too, I would think.