Yes; I do this to discourage people from making too many such posts, and making them too long. I don't want HN to turn into a blogging platform. Also, I wanted to make it easy to tell these posts from comments. If I made the text black I'd have to make it smaller, and then it would look just like a comment.

But I'm not wedded to the current way of doing things. I'd be open to alternatives.

It seems like this system punishes me, the reader, for something that the poster did wrong. If the poster is supposed to write his long rants on his blog and then link them here, the software should tell him. It shouldn't subtly make his stuff harder for me to read, because if I'm interested, I'm going to push through the low contrast text anyway.

Anyway, if you want to nurture the community, I don't think it's a bad idea to make the feedback deliberate. "This is too long, don't post it," will be a lot more effective than changing the color of the text.

Well, the lighter text does punish the original poster, indirectly. It lowers the likelihood of engagement by an audience and I like that subtle approach more than heavy-handed alert warnings. Sites that have that kind of approach feel like I'm in the principal's office and being scolded for no good reason. Subtle encouragement to do other types of behavior feels more like I'm in a hippie montessori school instead - we're not going to come down with the stick if you behave a certain way, but we're not going to give you the carrot unless you do better.

The fact that people are complaining about not being able to read longer blocks of text means it's working just fine. And it's a nice subtle touch - I never consciously considered why I tend to ignore rambling posts and stick to the discussion area instead until now.

I'm not sure it discourages long posts. The writer doesn't see it's gray until the text is posted.

Then limit the size of the textarea or something like that. It's bad usage, and saying that "it's a feature, not a bug" doesn't help.

Not sure that limiting the textarea would help - it's not like it constrains the length of these replies, for example. It's pretty trivial to compose a block of text in Textmate and paste it in, I'll often do that just for the spell checking or to make sure it doesn't get lost in submission or browser crash or whatever. (and often to review and make sure I don't post something I'll regret)

I believe that this form submits to a process on a server that could limit the number of characters that are allowed in the textarea.

That was in fact the post that triggered this one. I gave up reading it after the second paragraph.

However it was mainly because I wasn't interested in the topic, but had checked all the other articles out. There are some long self posts that are genuinely interesting to read and it still hurts my eyes to read them.

Maybe it should get progressively more grey then as you get longer and longer.

Very interesting idea. Do you mean each paragraph in a post gets lighter as it goes on or the color for the entire comment block fades depending on overall length?