Always apply boring and binaries files from _darcs/prefs direcory even if there are explicit settings for the corresponding prefs. There is no reason not to use these files. If there are explicit settings using darcs setpref [boring|binaries], these files remain the only possible way to set the appropriate settings personally at the repository level, and not globally.
This is one of my two patches that are related to preferences. Patches have no
dependencies on each other, so it will be two separate patches.
The full rationale for both patches can be found here: https://hub.darcs.net/ki11men0w/profile-develop/browse/presentations/darcs-boring-files.
If I understand correctly, this would mean that someone who wants to just
use the preferences chosen by `darcs setpref` would need to make sure to
delete the files in `_darcs/prefs`, or to have used `--no-prefs-templates`
from patch2231. I think that's fine, just want to mention it explicitly.