Fair question and apart from a rather vague sentence in the RFM, there is not much that covers that particular item, even in the factory teaching materials. (I have the older stuff, not privy to new and current stuff..)
I was wanting to see a diagram of what it does so I can answer that question in the oral part of the checkride, my CFI did say exactly what it says in 7-31 but being the diligent type, I wanted a colourful picture if it was available somewhere
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On the subject of typeratings, its the same over in the bizjet world where providers outside the factory training also have gaps in the material or when flying the aircraft you find out alot of stuff is “completion centre items” and hence your instructors have no clue what you are on about…