Ahh, yes.. that was it (we all discussed this earlier, I'd just forgotten the outcome).

There actually should be no issue in fsck'ing a filesystem that is mounted RO, except that certain errors require a complete unmount afterwards to guarantee consistency with in-memory data structures.

Under most situations, this will not happen, but when it rarely does happen, we could just reboot the player afterwards instead of always requiring full unmounts.

Mmmm... I wonder if this can be done inside Hijack without confusing Emplode?