Presently, WordPress appears to fill pages of comments by "fill first page of comments". This produces the following type of display: if 9 comments, Discussion set for 4 comments per page, and default to Last page (most recent comments), one gets:
Default page: comment 9 only
Page 2: comments 8,7,6,5
Page 1: comments 4,3,2,1
This makes very little sense to a visitor, who sees that there are 9 comments, but only sees one comment (#9) on the landing page, and must immediately page through the comments to even see #8.
Suggestion: Provide checkbox/method for a user to select "Fill Last Page of Comments". In this way, one "fills the last page fully, then fills the next page". This would produce:
Default page: comments 9,8,7,6
Page 2: comments 5,4,3,2
Page 1: comment 1
This occurs (non-threaded) in two plugins that are no longer being developed:
Paged-comments http://www.keyvan.net/code/paged-comments/
Paginated-comments http://www.badspiderbites.com/paginated-comments/
Thanks! --Bill