Earlier quoted context omitted.
The Ethiopian Airlines pilots followed the EAD to the letter. First, they attempted to adjust trim using electric stabilizer trim, and then upon realizing that the they were experiencing an uncommanded nose down stabilizer trim, they followed the runaway stabilizer procedure - namely, stab trim cutout and trim wheel grasp and hold. Afterwards, they attempted to adjust the stabilizer manually. There is a note in the E…
> Boeing did not instruct pilots to make sure to neutralize trim first using electric trim before doing the stab trim cutout. Yes, they did: "Initially, higher control forces may be needed to overcome any stabilizer nose down trim already applied. Electric stabilizer trim can be used to neutralize control column pitch forces before moving the STAB TRIM CUTOUT switches to CUTOUT. Manual stabilizer trim can be used bef…
The actual instruction is to follow the AFM Runaway Stabilizer procedure. That's exactly what the Ethiopian Airlines pilots did.