the lower levels of optimizations are supposed to be more straightforward translations of the high-level language code. you can imagine this might be useful if you are debugging assembly.
A proficient human coder, on the other hand, writes assembler that is partly optimized by default.
But few humans could write code like a seriously optimizing compiler, esp. on modern pipelined architectures - that stuff is unintelligible. Which is as it should be, because modern processors are not designed to be programmed directly by humans.