On Fri, 12 Nov 2010 16:23:58 +0100, Matthieu Lemerre <racin@free.fr> wrote:
> Here is first a patch that copes with this last point. Whenever you
> want to archive a thread, it finds whether you forgot to add a custom
> "user" tag to a message, and if so asks you for a tag to add before
> archiving. That way, I no longer have messages without any tags.

Hmm, this would be very irritating in my own workflow in which I really
only use a small number of tags on a fraction of my total mail archive
to differentiate mail type or content which can't otherwise be
determined from the indexed plain text of the message (I don't like to
add a 'notmuch' tag to mail from the list for instance since a saved
search for mail sent to the list address does exactly the same thing).

I agree that the spacebar does too much if you're just using a search on
the inbox tag and want something to stay visible even when you've
quickly spacebar'd through a thread and archived it, but in my case that
was easily solved by creating a new default saved search called 'todo'
which collects unread, manually tagged 'todo' and mail matching a number
of other criteria into one place.  When something has been followed-up
on, I remove the tag.

Colouring threads using notmuch-search-line-faces is also very useful in
that one-stop 'todo' view.

Would any of that work for you?  Why are plain text or header searches
not able to find the mail you're looking for?