display of comments underneath the articles is possible in 1.5 without a core hack as posted in http://compojoom.com/index.php/forum.html?func=view&catid=10&id=611 if the html is not echo'd but instead returned when using the event trigger onAfterDisplayContent.
see also this post:
http://forum.joomla.org/viewtopic.php?f=500&t=361560