Regarding #1 Engine continuing to run at the last commanded thrust based on loss of command, I don't believe that is the case, or at least maybe it differs for the control systems of different aircraft/engine combinations. I've experienced a CFM engine return to idle power due to loss of thrust command. The FADEC sends out a signal to an RVDT at the thrust lever in the cockpit, and the return signal (dependent on the position of thrust lever) is split into two parts which have to match each other within 2%. If they are not within 2%, signals from the channel not in command will be used, so long as they are within 2%. If the signals from both channels are out of range, then the FADEC commands the engine to idle. If the Aircraft on Ground signal is not available to the FADEC (ie the wire has been severed) then idle speed will be at flight idle rather than ground idle even when the aircraft is on the ground, for failsafe reasons.
I'll be interested to hear what the official details are...