Quoting karl@??? (karl@???):

> I usually don't use initrd/initramfs so I don't like that merge.
> Also I want to have the ability to unmounting /usr if I would whish.
>
> If it is to make all binaries to be accessible as /usr/bin/whatever,
> one could make links from /usr/bin/ to /bin for binaries in /bin
> instead of moving the binary itself and then linking.

Consider statically compiling any recovery / backup / maintenance
utilities required to work in /bin and /sbin even if /usr isn't mounted.
You might otherwise be unpleasantly surprised by items that fail to work
because of dynamic dependencies to libs inside /usr.

I've been pondering this matter for a while ever since the UsrMerge
notion and the Freedesktop.org kiddies' ritualised talking points (like
'Most distributions rely on initrds anyway...', 'Booting without /usr
is broken', and 'PulseAudio, NetworkManager, and udisks2 would break').
As someone who prefers to be able to maintain a simple small-rootfs
server system without initrd-dependency if he wishes to, I find that the
correct solution is to ensure that tools that _need_ to be in /bin and
/sbin (because they need to work without /usr) truly _do_ work without
/usr. And IMO the best way to ensure that is just compile them as
statically linked binaries.

(Want them packaged? Cool, create a mountutils-static package, etc.)