A design mistake in my comments form
It's slowly become obvious to me that one of the mistakes with the 'add a comment' form here on WanderingThoughts is that it doesn't show you the entry and existing comments. I know, a while back I thought that this was a good idea, but I've changed my mind since then; it's a design mistake.
Why I know this is pretty simple; I base it on personal experience. Whenever I write a comment myself, I invariably wind up with two windows open, one showing the existing entry and comments and the other one for writing my new comment. And these are real windows, not tabs, because I need to see both the comment draft and the current entry plus comments at the same time, which means that they consume quite a lot of screen space.
If I find myself using a workaround all of the time, it's pretty strong evidence that the design is wrong. Good design doesn't need you to fix things for it, it just works. Conversely, the use of workarounds means that the design still has friction points left, places where it doesn't really work right and users have to fix it themselves. Clearly this aspect of my comment system falls into the latter category.
The friction imposed by this design might be worth it (or even desirable) if I had hordes of commentators who would otherwise quote things all the time, but I don't; if anything I have the opposite problem. That makes the friction an unnecessary annoyance and thus a design mistake.
One of the lessons I draw from this is that designs for high volume, high activity sites are not necessarily appropriate for low volume ones. In a way I knew that already, but it hadn't necessarily sunk in that this applied to inobvious things that seemed like good ideas when I first heard about them as well as to the obvious stuff that was clearly too complex for my modest needs.
(DWiki's comment system was not deliberately designed to not show the original page you were commenting on; it just happened to be the easiest way to set up the 'write a comment' template way back when. At the time I did this I didn't think it was important either way, and then later I came to think that it was a feature. Now it's clear to me that it's a mistake, one not justified by other needs.)