That’s certainly critically important advice. However, it would seem that if an engine (at full throttle, which it would be in most partial engine failure modes) drops rpm to 1000 - 800, it ain’t really “partial” engine failure anymore. Also, one needs to be cautious about reacting too reflexively and feathering the wrong engine, thus the mantra “identify, verify, feather”. It only takes a few seconds. Still, if you see the rpm falling rapidly, get it feathered.
Yes. In training I used to hurry, hurry, hurry. Now being older and wiser, maybe, I say first and most important, fly the airplane. Then methodically identify, verify, and feather. If the engine is still idling along, I would be inclined to spend a few moments trying to decide why it is doing that before killing it. There’s a point in rpm also where it is neither providing thrust or drag. Know what that is. Decisions, decisions in multi flying. And instead of dead foot, dead engine, instead just determine which way the plane is trying to turn…which leads to the dead foot anyhow.
Urgency is in maintaining control…old saying about first step in an EP is “wind the clock” to keep your hands off anything important until your (and co-pilot’s, if applicable) brain(s) are fully engaged.