@foone By the same argument, you burn your brain out if you use good grammar.
What actually goes on is this: you learn how to write clear, maintainable code through practice and self-examination, and then it becomes a habit, so it takes no effort at all.
For example, I use assertions quite a lot when I initially write code, just so they go off if something goes wrong. I don't even think about it as I do it. Later, I remove most of them because they're clearly redundant.