David is quite accomplished, but in this instance he is simply wrong. For two reasons:

1. All the reasons he cites that depend on "what the metal does" being different and quite a bit more complex than what is surfaced in C apply equally to machine/assembly language. So the CPU's instruction set is not a low-level language? Interesting take, but I don't think so: it is the lowest level language that is exposed by the CPU.

2. The other reasons boil down to "I would like to do this optimization", and that is simply inapplicable.