Sometimes a bug report is a labyrinth. #348046 is an example of this. It is a horrible mess of at least three different issues with half of the original participants having become unresponsive. I would like to pull the issues apart into different bug reports to be able to deal with them (and their probably unresponsive submitters) individually.
Obviously, cloning and renaming is not an option since this copies the mess.
So, it would probably be desireable to download the bug mbox and to bounce individual messages to new bugs (that have been created before), but the BTS recognizes the dupes and bins them. Blars has helped me by looking at BTS mail log, so it was clear that removing the X-Loop, X-Debian-PR, X-Spam, Resent- and Received headers from the mbox before loading it into mutt to do the actual bouncing works fine.
A command line to do this:
rm -f mboxout; < mboxbug formail -d -I Received -I X-Debian-PR -I X-Loop -I X-Spam -I Resent -s >> mboxout
After trying this in "production", one needs to send one message per BTS pulse, or one will totally mess up the order of the messages. That's a real pity and an annoyance.