First, a note: the link I provided in my previous post is now broken, and its target has been replaced by something that is not germane to this discussion, but you can currently find the relevant part of the checklist in [1].

On first reading, I also thought the quoted passage from the AD was an instruction to use the yoke switch to re-trim before cutting out the stabilizer trim, but the following sentence (also quoted above) makes it clear that it is not: it is actually part of a statement about what options are available to adjust the trim before and after the switches are set to cutout. I feel sure you will try to argue this point, but I am pretty confident that this is the correct reading, because the checklist has no mention of delaying trim cutout. This is very significant, because the checklist is what pilots are trained and expected to follow (and, furthermore, I believe this checklist is a 'memory item' - one of the procedures that pilots are required to be able to perform from memory.) Nothing in a checklist should be incomplete or ambiguous, nothing of consequence should be taken as read, and if anything is, it is a more serious matter than poor wording.

And the checklist is unambiguous about what to do: if the problem persists after the autopilot is disengaged, use the trim cutout, and thereafter, trim manually - this is what the crew experienced, and this is what the crew did.

It is quite clear from the documentation that the manual trim wheels were regarded as an adequate means of adjusting the trim if the electric trim was cut out. Once the pilots found that this wasn't working, they did extemporize - they re-enabled the electric trim - showing that, contrary to what you insinuate, they did understand what the switches do.

You have set up a false dichotomy between pilots acting as robots and being able to extemporize a solution to every problem from first principles. The reality is that aviation has achieved its unprecedented level of safety by, in part, by considering a great many things that could go wrong and figuring out the optimal responses, taking into account that these responses must be made in a stressful and often degraded (informationally, functionally, physiologically) situation. Pilots are trained, and expected, to execute the documented procedures promptly, and only deviate when the situation demands: extemporize on a check ride, and you are likely to fail. This is not mindless bureaucracy at work: it is the rigorous application of hard-learned lessons. At the same time, they are also expected to know their airplanes thoroughly so that they can respond to unanticipated problems, and this is precisely why they were annoyed at not being told about MCAS.

So, to summarize: 1) by their actions, the crew demonstrated that they were up-to-date on the procedures that nominally incorporated the lessons from JT610; 2) by their responses to a problem with this procedure, they demonstrated that they did understand what the switches did and how to use them. Undoubtedly they did not figure out what they needed to do as rapidly as you would have in their place, but it is unreasonable to fault them for that.

I recently learned that, prior to the Max, the trim wheels were so rarely needed that their use was no longer part of simulator training, and the diameter of the wheels was reduced on the Max, yet here we have an AD saying you can use these wheels to trim the airplane when the electrical mechanism is cut out, and item 6 on the checklist explicitly says to do so. Elsewhere in the AFM it notes that the trim wheels can be hard to move in some circumstances, but if you are going to fault the pilots for not connecting the dots, then it applies doubly so for the people at Boeing and the FAA tasked with writing and certifying the procedures for handling an MCAS failure, who all apparently overlooked something that was obvious to you just from reading some newspaper articles.

At this point, the more you argue that an effective procedure for dealing with MCAS runaway was obvious following the JT610 inquiry, the more you indict Boeing and the FAA for not making it explicit in their response.

[1] https://www.businessinsider.com/ethiopian-airlines-et302-boe...