Michal Jaegermann (michal@harddata.com) said:
Well, Lennart says explicitely that with systemd and /usr mounted on its own file system things like audio, or printing or plug'n'play will not work and that he does not care as they were broken anyway. Maybe in some of his warped universe as I can assure you that up and including Fedora 14, and with /usr like the above, all these things do work just fine.
Essentially, you have to ensure that everything called during the boot cycle up until the point that /usr is mounted, including any and all programs called from udev rules, have all the libraries, configuration, and data they need to write to, available on the root partition. (*)
It's something that certainly can be made to work where problems are found, with enough effort - that would be auditing that would have to be done on each release (potentially each update!). So, then it's a cost-benefit ratio, and weigh that at against the usage case of separate /usr (which is.... ?)
Bill