Actually it doesn't link to the guidelines. It links to

http://ycombinator.com/newswelcome.html

I added this feature within the last year, so none of the established users know it exists, but I think it has helped stave off decline as HN has grown.

You should add a bit of space between the edge of the beige and the text.

Yeah, you're right. The original intention was to make the beige almost invisible, so that it just added a subtle impression of a box bounding the text, but it isn't really working that way.

It works better on pages with images that are flush with the beige on both sides. If you indent the text, what do you do with the images? Indent them too? Maybe.

The 'welcome' link is hard to find. It does little to explain things like flagging, the karma limit to down or up voting and in general, anything at all. In fact, it doesn't even tell you the format rules the HN comment box accepts. There is conceivably some deluded notion that 'real' hackers will sort all of this out. Or they'll just call terrible UI as they see it.

If you look at the FAQ at the bottom, one of the question/answers has a link to the formatting rules.

http://news.ycombinator.com/formatdoc

Thanks, I've been curious about how that worked ever since I signed up!

What are the thresholds for voting down a comment? I looked in News News and it says karma of 100, but there must be something else because I have over 100 now and I don't see any down arrows.

I think it's around 200 now, it increases over time to deal with karma inflation.