Originally Posted by CNexus
No, even with an unlocked bootloader you can't flash unsigned firmware. You can directly flash to *some* partitions, but that's it.
That's the point. You can flash unsigned images to system, recovery and boot, those are all you need
. You bork any or all of those and it is easily recoverable. You shouldn't EVER be flashing unsigned firmware to radio or hboot. You're just asking to brick your device.
There is absolutely no situation where s-off is safer than having an unlocked bootloader.
Unlocked bootloader and you want to flash a kernel but make a simple typo:
fastboot flash h
boot boot.img ---> no consequence
S-off, you make the same typo = brick, unrecoverable unless you JTAG
Lets say you're working on CM and you're initially setting up your partitions on a new device. There is a bug in vold that returns incorrect partition numbers and you're s-off. You boot up, it automatically mounts your radio partition or hboot as your internal or external storage. Your device then writes to one of these partitions -> brick, unrecoverable unless you JTAG. If you are only bootloader unlocked, you get an error that you can't read or write the partition and investigate further with no consequence.
I've seen both of these situations occur and result in bricked devices.