We've recently rolled out Confluence, and I notice that often a new user will use the "comment" feature, when it would work better to insert their comments (perhaps in italics, possibly signed) into the page itself. When someone throws out an idea in a new page and notifies others to take a look, the natural new user inclination is that those looking will use the Comment feature.

Comments can't be edited, so if a part of the comment becomes obsolete or wrong, you can't fix it (without creating a new comment and deleting the old.)

Comments can't be interspersed with the existing text, so sometimes the context of a comment is confusing or has to be explicitly stated rather than implied by its location as an edit would.

Replies to comments can't be interspersed with the original commenters' thoughts.

How to improve this?

If a person has edit rights to a page, and selects Comment, put up a page that suggests they may want to consider using Edit instead, (listing justifications such as above). The user would be able to configure their profile to suppress this notification after they "get it."

If a page is "brainstorming" type of page that expects lots of discussion, it might also be useful to tag the page to only permit comments from users who do not have edit rights.

In summary, the only real advantage to comments that I see, is in a high volume situation where comments don't result in concurrent edit conflicts. In smaller organizations, conflicts may not be a big enough problem to justify it.