The --incremental (udev) call refuses to (re)add a temporarily disconnected members back to an already restarted (active) raid.
Even though the refusal may in the future only happen for obvious conflicts (Bug #1088532), there is still an option missing to --force the addition anyway.
Using --force with --incremental (where mdadm will still apply sanity checks to not add it to a completely wrong array etc.) seems much less dangerous than forcing the user to have to --zero-superblock around in the system.
The --incremental (udev) call refuses to (re)add a temporarily disconnected members back to an already restarted (active) raid.
Even though the refusal may in the future only happen for obvious conflicts (Bug #1088532), there is still an option missing to --force the addition anyway.
Using --force with --incremental (where mdadm will still apply sanity checks to not add it to a completely wrong array etc.) seems much less dangerous than forcing the user to have to --zero-superblock around in the system.