Can you collapse random mails in OSX into a single conversation?

Question

In MacOSX, using the standard Mail.app, you can turn on mailbox threaded conversations, where all the mails for a conversation are collapsed into a single row and can be expanded. When using the mutt email client I configured a macro which allows me to tag several mails and then force them collapse into the same thread by setting the Message-ID header into all of them. Does such a plugin exist for MacOSX's mail application? Here's the mutt feature http://www.mail-archive.com/mutt-users@mutt.org/msg18310.html by Ulf Erikson.

Exactly what I'm trying to accomplish is select two random messages in my inbox (on IMAP server) and force them into a conversation. Also, select one and break it out of the conversation. I've been using this in mutt for ages in mailing lists, where sometimes people would reply to a thread changing the subject (there I would split the conversation thread). Or when I would receive several automated mails like "You bought this!", "We are billing you", "Here's the bill" collapse them into a conversation even though they are individual and come from different addresses without any filter rule-able pattern.

Answer 1

Silly me, since I'm using IMAP folders I configured mutt on the server, run ssh into the mailbox and use the handy macros to modify the offending mails. The only drawback is that the macros actually work by deleting the old mail and creating new duplicates with the modified headers, and MacOSX's Mail re-parses them for filtering rules so I end up with duplicates in local archives. Still, I'm looking at a much more cleaner inbox now than previously.