Why did I just get multiple invites and cancellations for the same meeting? Is this thing on?

A while back I posted about common ways meetings can go missing, one of which is when a distribution list is invited to a meeting.

Today I saw an interesting 'feature' of how inviting a distribution list (DL) then trying to make changes later can really confuse things.  Our team got two invites and a cancellation to the same meeting, and the organiser couldn't work out how it had happened.

http://support.microsoft.com/?id=222388 covers the basics of what the organiser and invitees see, but it doesn't really explain how that occurs. So for the record, here's a worked example (you know how I love those):

• I've been asked to create the invite for my team's offsite team-building exercise (read: we're going to the pub)
• My team are all members of a DL called BigTeam, so I send the invite to them (ignoring the great advice I usually encourage everyone else to follow that says never invite a DL without expanding it, especially one you're a member of)
• I realise later that the BigTeam DL also includes some guys who work at a remote location to us - remote enough that they probably don't want to know the details of some drink-up they won't be able to get to. So I go back into the meeting and remove them.
• Here's the critical bit: because they were invited as part of the BigTeam DL, to un-invite them I have to expand out the DL, then remove them from the expanded list.
• Here's the bit they don't explain in the KB article: Outlook just sees addresses in the invitee list. It doesn't much care if they're DLs or individuals. It sees that the BigTeam DL has gone from the invitee list, and a whole load of individuals have suddenly appeared. (It just sees the difference between how the invitee list looked before and how it looks now, so isn't 'aware' that a DL was expanded to get to where we are now.)
• Outlook does what it always does in these situations: it sends a cancellation to all the addresses that were in the invitee list but aren't any more (i.e. the BigTeam DL) and sends an invitation to all the addresses that are in the invitee list that weren't before (i.e. the people whose names are left after I removed our far-flung colleagues).
• Everyone gets a cancellation (because a cancellation was sent to the BigTeam DL), and those lucky enough to still be invited get a new meeting request. It doesn't appear to make sense, but this is Outlook behaving as it was designed.

The up-side if you're using Outlook 2007 is that at least it doesn't allow you to process meeting invites/updates/cancellations in the wrong order, which would probably confuse things even further. But the basic behaviour is still the same.
I hope this helps explain things if this has been causing you the same kind of confusion it caused in our office today!