Like a few other people, I occaionally (very occasionally) receive encrypted emails. So far that was not a big deal, because mutt can automatically decrypt these emails, and also search in encrypted emails (by decrypting them first). However I plan to change my email setup in the near future, and allow other programs (like Thunderbird or a mobile client) access as well. This does not work well if the emails are still encrypted. Besides, the emails reside on an encrypted filesystem, there is no need for another layer of encryption on disk.