I don't have any issue with a browser extension. The problem is that the actual CONTENT of the discussion is changed because comments aren't collapsible by default. In many of the comment threads I look at, 80% of the discussion is on the top comment, even though it may be only mildly more interesting than the second highest rated comment.

Are you saying that his points about how non-collapsible comments shape the discussion topography are not valid?

I said no such thing. I said I didn't understand. I take he is saying top comments tend to get more up votes? I dismissed that because it's obvious and wondered if he had another issue. I assume everyone is using a browser ext to collapse expand.

reddit has hot/new/rising/controversial/top but I've haven't found a great need for that personally.

Actually I'm saying that top comments don't get more upvotes. Once the single top comment has enough discussion underneath it, the comment votes become skewed and inaccurate. At that point, the "top" comment (which may or may not be the "top" comment anymore) gets an unproportional amount of votes with respect to it's vertical location on the page.

The second, third, and fourth comments may be great or even better than the comment at the top of the page, but they don't get any discussion because they are too far down the page.

Sure, using a browser extension fixes that issue for me, but it doesn't change the fact that 80% of the discussion and exposure is only going to happen on the first thread.

I expect there is a good reason why HN has chosen not to implement comment collapse. I posted this question in hopes of getting an answer as to what that reason is. Maybe if I understand the system better then I will be able to use it more efficiently.