The code got removed by accident during the cleanup in commit 9c438bcac671. So this patch is needed to bring it back and make things work like documented:
--- src/daemon/main.c (revision 27898)
+++ src/daemon/main.c (working copy)
@@ -892,7 +892,8 @@
+ if (conf->high_priority)
if (change_user() < 0)
Patch committed, thanks!