Lots to consider - glad you all have better overview than me.
Yes, perhaps better at tce-setup line 144.
For non-boot calls ... I'll have to find a cheap test that fails at boot time but not after.
EDIT: Ah, and use /bin/rmdir for busybox instead (thanks, bmarkus)
EDIT: to let tce-load rmdir when not boot time, my first reaction is to pgrep. I imagine there is an easier test, though.
[ ! "`/usr/bin/pgrep tc-config`" ] && /bin/rmdir /mnt/test 2> /dev/null
And put the same line, without test, at tce-setup line 144.
FWIW