First of all, is it possible to fetch entries from the journal of some one other than yourself via the getevents mode? Or is there some other mode that would be more appropriate. Getevents appears to only allow you to fetch your own journal. (currently it looks like my wisest choice is to simply use the /data/atom format)
Secondly, having fetched the journal entries of the friends, and the journal entries of any shared journals, is there a mechanism for exporting the comments of those friends journals? Currently the data/rss and data/atom formats don't even appear to inform you if comments are present on a given entry. And the comment export guidelines clearly state that you can only export your own comments.