[gowld]

That's the claim, but not an explanation. HN isn't multi-color.

[devastora]

You have a point. But even though HN doesn't have a ton of color, it still feels different on grayscale I think.

Most of the evidence is anecdotal, but it seems to work for a lot of people (myself included). I went into it more here - https://news.ycombinator.com/item?id=17133984