Giorgos Keramidas writes:
> On Sat, 06 Jul 2013 17:44:30 +0200, David Engster <deng@randomsample.de> wrote:
>> AFAICS in `nnimap-retrieve-group-data-early', the resync should only
>> happen when there's either no 'active', 'unexist', or
>> 'uidvalidity'. Perhaps the first step should be to install some verbose
>> messaging which says which of those triggers the resync.
>
> I can try that.  Thanks for the pointer.

You can apply the attached patch against current Emacs trunk to see in
the *Messages* buffer why a group is triggered for resync.

-David