That's simply measuring the wrong thing altogether. Lines of code per day produced is simply not a valid metric at all. It's just a bad metric period no matter what number you put on it. You cannot measure the quality of a dev by the lines of code he produces, at all.
if (false) {
// my daily 20 lines here
// ...
}And I'm saying that's still a terrible measure and not accurate. LOC is simply not a valid statistic to even look at. It's an example of lying with statistics; you could take a thousand good developers and you'd probably find their LOC per day counts all over the board. The amount of code you write is not a measure of how good a developer you are whether it's high or low. That's not how you measure a good developer.
The OP is trying to say looking for high LOC counts are not a measure of a good developer, and he's right; but he's failed to realize yet that the metric itself is what's bad, not the values derived from it.
Good developers don't have to be highly productive, but they might be; what matters are the results of their efforts. Do they produce good programs, with few bugs, that age well over time, and are easy to change to adapting circumstances. Good developers write good code; some write more than others, but LOC tells you nothing about how good a developer is whether that number is high or low.
Like any writing, it's the quality of the code that matters, not the quantity. You cannot measure quality by looking at quantity.
Writing is not the best analogy -- because of the typical churn-edit cycle -- but to use your example, of course reaming out pages of text in one day will, on average, be of a lower quality than a virtuoso author who carefully chooses his/her words and maybe produces, on average, a paragraph a day. If you were to tell a layperson that a good writer can output a paragraph a day, they'd probably find that counter-intuitive because it's such a minute amount; "Surely anyone can write a few sentences in eight hours? Even I could do that!" They're making the same false-entailment, without seeing the craft that went into those paragraphs/day, or realising that there will be days when said author writes nothing and others where they're in the zone and write an almost-perfectly-formed chapter. That doesn't stop "paragraphs/day" from being a bad metric, nor does it imply that anyone who writes a paragraph a day will end up with anything good.