Sorry -- unclear on a couple of points:

On Sat, 12 Jun 2010 09:22:29 -0400, Jesse Rosenthal <jrosenthal@jhu.edu> wrote:
> 2. You could brute-force it. Include a nm_dump file as one of your
> unison paths, along with your Maildir, then always run:
> 
> notmuch dump > nm_dump
> unison

You have to run "notmuch new" here.

> notmuch restore nm_dump

> If you take a bit of care in how you tell unison nm_dump files...

I meant, of course, "how you tell unison to merge nm_dump files."