I've noticed that a lot of people are using e.g.:
mail_location = maildir:/var/vmail/%d/%n
Then either they don't have home directory set, or their home directory is the same as the maildir. http://wiki.dovecot.org/VirtualUsers/Home explains all the problems of not separate home and mail directories.
Also whenever I try to suggest using a separate home and mail directory, the answer is way too often: "But I'm using virtual users. (They don't have home directories.)"
So I started wondering. Maybe simply renaming the "home" to something else would help here at least some. Make all of the documentation use only the new word, and add alias for userdb so that the new name and the "home" both work (I guess docs would need to keep using the "home" as field name for some more years).
So far I've only come up with "vhome" as the replacement name. Other ideas?