Roman Ivanov wrote:
In a tree-like forum, a discussion can be extended at any point, and the bigger the thread grows, the more points there are. It's more difficult to keep track of, and it's /much/ more difficult to see the "current" state of an entire discussion that you haven't read from the start. You can't just read the last 10-20 messages, because they could be from entirely different, unrelated branches. Linear threads insure that users are on the same page of a topic, both figuratively and literally.
With a competent newsreader, this is no trouble at all. Read message subjects are greyed, so there's no problem seeing the current state. With the linear ones, I often have trouble figuring out what people are replying to.
