Why are many threaded comment systems so bad? It seems pretty clear to me that you need a couple of things to have a workable threaded comment system:

  1. The ability to present long sequences of replies in a readable fashion.
  2. The ability to collapse comment threads.

If you lack either of these, comments threads become horrific if you accumulate more than a few comments. As an example of abject failure, consider the comments on Wordpress blogs.1

You can have precisely three replies in sequence before all comments are shown at the same level (destroying the replied-to relationship), and comments are squashed to fit into ever-smaller portions of the blog’s column-width, which makes long chains of replies truly long in terms of how far you have to scroll to get past them.

This excacerbates the latter problem. If you’ve decided you’re not interested in a thread, there’s no way to collapse them, and so you’re left to scroll furiously, while keeping an eye out for a break in the rightward march that signifies a new thread. It’s also very difficult to get context for a comment that appears after a long sequence above it - which comment was it replying to? That suggests that you probably need a way to collapse the thread above a comment, a feature which I’ve never seen anywhere.

The site I’ve seen which comes closest to doing this right is probably Reddit: you can collapse threads; and if a series of replies becomes too long, it gives you a link to continue it in a new window.2

Arguably, if you’re generating the kind of discussion that SSC gets, then what you need is a forum, not a comment thread. But most forums don’t actually have threaded comments (except Reddit), although they do tend to have much wider text areas, which mitigates some of the problems.

Anyway, Disqus comments seem to be reasonably okay for small volumes of comments, but I’m just surprised that this problem isn’t solved well more often.

  1. If you’re looking for an example, have a look at any of the posts on the rather wonderful Slate Star Codex, which always generate a lot of comment. 

  2. This still seems kind of a pain, but I haven’t thought of a more ergonomic way of doing it.