Commenting form should not be shown to users that has no rights to post comments. In PageComments class there is method "isAllowedToPost" that check is user has right to post. But in case where there are no comments posted, it returns true value so form will be shown to all users.

public boolean isAllowedToPost() {
if (getThread() == null)

else

}

Maybe this feature is planned to restrict posting comments to some of users by checking user rights to post on specific comments thread but in that case maybe there is need of another method that will be used in comments.inc.ftl only for showing the form.

If that is not the idea, this method should only check user rights for all comments thread in forum.