The case for the /usr merge

Quite. I moaned about this when it was first mooted, but on further analysis, I was wrong. So this means a tiny bit of futzing with your initramfs to boot /usr early. Big deal. (A bigger deal is that busybox mount could historically not handle as many filesystem options as real mount, so if you were using busybox mount, you had to mount filesystems with an artificially limited set of options, then remount them with different options once you'd switched roots. I'm not sure if this has changed in recent versions of busybox mount or not.)