ive been following a few topics now where some of the posters don't respond for 12-24 hours then when they do come back and respond they quote one post, then a second, then a third etc and you end up with 3-5 posts from the same person in a row
http://www.geekzone.co.nz/forums.asp?forumid=48&topicid=154324&page_no=5#1162614 for example
i just find it makes a thread longer and more messy
having a multi quote button would allow users the ability to select multiple posts they wish to quote. when they have finished selected they could either hit quote on the last quoted post or hit compose new reply and all the quoted material would show up so they could compose their replies.
failing that you could make it so that if they make a post within say 30 minutes of their last post and no one has posted after their last post it automatically adds it to the bottom of their last post.
i dont know if its possible but just spinning ideas