> From that argument, we should be coding everything in hand tuned assembly, because hand tuned assembly gives a 10% to 200% speedup over C.
Yes, all things equal, it's better to write faster CPU-bound code. In a world in which writing optimal machine code all the time was possible without sacrificing anything else important, then we would always want to do it. This is hardly a controversial conclusion.
The reason we don't write faster CPU-bound code is that, in the world we live in, all things are never equal. Correctness, security, maintainability, development velocity, portability, engineering culture/trends, and so on are usually more important than raw CPU performance.
Yes, all things equal, it's better to write faster CPU-bound code. In a world in which writing optimal machine code all the time was possible without sacrificing anything else important, then we would always want to do it. This is hardly a controversial conclusion.
The reason we don't write faster CPU-bound code is that, in the world we live in, all things are never equal. Correctness, security, maintainability, development velocity, portability, engineering culture/trends, and so on are usually more important than raw CPU performance.