When you write code do u always write the best most efficient code possible ( which is impossible and time consuming)or do you write code to just do the job?
sometimes one, sometimes the other.
If you write your code with C and it accomplishes the task why on earth you need to check the compiler output to see if it was better than hand assembly or not?
I do not, if stuff is extremely time critical, I do not bother with C.

I have applications varying from 100% C to 25% C and the rest in assembler. E.g. when mixing colors I must display a 160*16 sign in 1 ms and no C code can keep up with that.

That said, often the approach is much more important than the language. E.g. a table driven lookup in C can be much faster than a calculation in assembler.

Erik