"The compiler" and "The optimizer" are doing a lot of the heavy lifting here in the argument. I definitely know compilers and optimizers which are not that great. Then again, they are not turning C++ code into ARM instructions.
You absolutely can fool a lot of compilers out there! And I am not only looking at you, NVCC.
But the point should be to follow the optimization cycle: develop, benchmark, evaluate, profile, analyze, optimize. Writing performant code is no joke and very often destroys readability and introduces subtle bugs, so before trying to oursmart the compiler, evaluate if what it produces is good enough already
You absolutely can fool a lot of compilers out there! And I am not only looking at you, NVCC.