Okay, I had to look up that word 
I have tried this using a RAID card over a decade ago with two mirrored drives and while it worked when I disconnected a drive to simulate failure, for me it comes back to what if the bootstrap code is corrupt and the system freezes or is stuck in a loop. That RAID card can’t help in that situation (that I know of) and I’m certain there is something out there to combat that called IT technical support (and you might be that support).
Since I was brought into this conversation, my two cents are:
- Maintain a current backup of your TrueNAS configuration file.
- If you are really worried about the time it takes to bring your system back online, you can create a bootable USB Flash drive with TrueNAS installed and then you restore your configuration to it. But it still requires some manual operation to get the system back online, it is not fully automatic.
- Never assume something will work as you think it will. Test it out to verify it works as intended.
Cheers