Thanks for that Wolf, I was recently discussing this A-400 incident with a current HH-60 pilot and he said the same thing- they were comforted to know that they could mash the levers forward and bypass the electronics/FADEC if need be- a mechanical bypass. Likely part of the legacy inherited from the original post-Vietnam battlefield helicopter requirements.
There is some confusion of terms here.
A FADEC is exactly that: "Full Authority Digital Engine Control". Fuel to the engine is entirely metered/controlled by a digital computer. This function resides in an electronic box often called an ECU, which often has many other functions besides metering/controlling fuel flow. The pilot controls thrust by providing an electronic input to the ECU, which then varies the fuel flow to deliver the thrust demanded by the pilot.
The T700 engine does
not have a FADEC. It uses a hydromechanical fuel control system (HMU). The HMU uses many mechanical and analog inputs to meter/control the amount of fuel going into the engine. One of the inputs to the HMU is an electronic unit which provides much finer fuel control and also adds many protections and other features. The PCL can be used to lockout the electronic inputs to the HMU, but the PCL does NOT give the pilot control of engine fuel flow. It only gives the pilots the ability to eliminate the electronic inputs to the HMU. The PCL is NOT a "mechanical bypass" to give the pilot mechanical control of engine fuel flow.
Keep in mind that helo engines are designed to maintain 100% RPM at all times. In a helo the pilot does not change thrust by changing RPM. He changes thrust by changing collective on the rotor system. So the pilot NEVER controls throttle/fuel flow to the engine. He can only control (via the collective) the load put into the engine/drive system and the HMU then controls fuel flow to maintain RPM. There is no link (either mechanical or electrical) between the pilot and the HMU for him to directly control engine fuel flow.