You might as well be able to extract a method with a meaningful name then.

Please no. Don't extract methods methods just to avoid using a comment. You end up making code more difficult to follow when you do that since you're now jumping somewhere else in the file and you're adding a lot of noise by having to pass the function's current state along as arguments to the new function.

>by having to pass the function's current state along as arguments to the new function.

But then the state being read and mutated by a block of code is explicit. The alternative is having to inspect the code to determine if and what state is being manipulated. The more code in a functional unit, the harder this gets.

If you're mutating variables then I'd agree that it might be best to encapsulate that in a function. But I'd argue that except for performance sensitive code, that's bad practice. The vast majority of code I write has 95% immutable variables. So even in a large function they'll typically be at most one or two mutable variables to keep track of (and very often zero).

That then makes the code non-linear, which IMO makes it a lot less readable in most circumstances.

It depends, if it needed a comment in the first place it likely was at a different (likely lower) level of abstraction than the rest of the code in that method.

Yes, but that doesn't mean it doesn't benefit from being inline. I love being able to skim over the paragraph-comments to get the big picture and then dip into the details without having to jump to another file / part of the file and lose my context.

To me it's actually faster and easier to read code instead. This is because i generally don't trust "what" comments - either I know the code already or I don't, and if I don't, then I don't trust the "what" comment fully, so I both have to parse "what" and code.

A "why" comment usually ages well, so I generally trust it and can use it to better parse the code and its intentions.

So I belong in the "what only for API methods" camp.

Do you also read through every function call (at least the first time you encounter a given function)?

This is Damian Conway's "coding in paragraphs" advice, and in my experience, it's the single best advice for more readable code. When you have a large function, split the code into blocks with a heading comment on each section. That way, you can skim through the function body quickly by just reading the headings, then dive deeper into whatever block you're interested in. Like section headings on an article.

I do something like this, but I write them as debug log statements so that you get the additional benefits from logging.

Yes, I've also done this in places. It works pretty well, although I wish I could get my syntax highlighter to de-emphasise these lines like it does with comments.