Hi Jamie, Austin,
* Jameson Graef Rollins <jrollins@finestructure.net> [25. Jan. 2012]:
> On Wed, 25 Jan 2012 20:19:03 -0500, Austin Clements <amdragon@MIT.EDU> wrote:
>> One very common cause of this is someone using "reply" to get an
>> initial set of recipients, but then replacing the entire message and
>> subject (presumably without realizing that the mail is still tracking
>> what it was a reply to).  This can also happen if someone
>> intentionally replies to multiple messages (though few mail clients
>> support this), or if there was a message ID collision.
> 
> This is a very common occurrence for me as well.  I would put money down
> that this is what you're seeing.

I thought about this too and this is why I checked for any
occurrence of Message-IDs in the other emails: 

   |> I isolated the thread I was interested in,
   |> extracted the message ids of its messages and greped the rest of
   |> the messages for this message ids: no matches.[2] Therefore no of
   |> the rests messages are part of the thread I was interested in

perhaps there was a logic error in how I did this:

   |> [2] grep -I "^Message-Id:" /tmp/thread-I-m-interested-in.mbox |sed -e "s/Message-Id: <//I" -e "s/>$//" >really.mid
   |>     grep -I -F really.mid rest.mbox
   |>     --> no match

/tmp/thread-I-m-interested-in.mbox  is a mbox with messages
I'minterested in, the "real" ones.  really.mid is a list of
Message-IDs of these "real" emails.  rest.mbox is a mbox with the
other emails, Emacs showed in his notmuch show buffer but are
other threads.

Since there is no match I concluded, the threads are not linked.
Perhaps I made a mistake.  I'l retest it and report again.  But
right now I don't have the time to do this.

Ciao, Gregor
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