David Bremner <david@tethera.net> writes:

> How is the performance of tree-view on these threads?

tree-view?  Loading is about equally slow with/without
notmuch-show-indent-messages-width=0.  Navigation is pretty fast once
loaded.  "notmuch show --format=sexp" for an 1100 message thread with
7.5 MB of non-attachment takes 0.5 seconds.  This thread is much too big
to display in a normal Emacs buffer, though I can see specific messages
fast using C-u (notmuch-search-show-thread ELIDE-TOGGLE).