As someone who writes assembly, I think this is overstating the case. There are a lot of algorithms (particularly short ones) where good C compilers generate n

As someone who writes assembly, I think this is overstating the case. There are a lot of algorithms (particularly short ones) where good C compilers generate nearly optimal code that you would be hard-pressed to improve on. In my experience the benefit you get from writing assembly comes largely from your ability to do better register allocation for your fast-paths, in cases where your compiler would spill registers to the stack. There are cases where the compiler does something that is genuinely stupid (http://blog.reverberate.org/2011/03/19/when-a-compilers-slow-code-actually-bites-you/ http://blog.reverberate.org/2011/03/19/when-a-compilers-slow...) but in modern compilers these are pretty rare.