So, what does actually happen when, in a type like the B737, you hold a particular attitude - against the feel forces - then run the trim. Do the forces reduce to zero, or do they stay the same?
It is quite simple and the linked article is I guess correct but kind of a storm in a teapot. If you hold the elevator forward in that go around example, say 2kg (just an example) of force is required, to hold 15 deg nose up, if you trim down and continue to hold about 2kg the aircraft will pitch down. If you trim down and reduce forward force commensurate with the trimming (allow the control column to return toward the centre) then the aircraft with remain at 15 deg nose up (all other things being constant of course).
This is because the Elevator Feel System will generate a simulated aerodynamic force for the commanded elevator position and airspeed (and stab position, but how much and in what way isn't documented). As you centralise the control column then the elevator is centralised but the pitch maintained by the stab position.
So if you hold a set pitch attitude and trim then you will need to relax the pressure on the control wheel - the article seems to be making the utterly intuitive reflex an issue.
The article then criticises this:
To recover from a stall, angle of attack must be reduced below the stalling angle. Nose down pitch control must be applied and maintained until the wings are unstalled. Application of forward control column (as much as full forward may be required) and the use of some nose-down stabilizer trim should provide sufficient elevator control to produce a nose-down pitch rate. It may be difficult to know how much stabilizer trim to use, and care must be taken to avoid using too much trim. Pilots should not fly the airplane using stabilizer trim, and should stop trimming nose down when they feel the g force on the airplane lessen or the required elevator force lessen. (my emphasis)
It is absolutely correct. To recover from a nose high condition, the elevator may not be sufficiently effective. It says "the
required elevator force lessen". In other words the amount of deflection (i.e force) required to reduce the angle of attack sufficiently to break the stall or recover.
For example, if you try the Turkish AMS event in the sim, recovering from the stall requires immense amounts of forward pressure to prevent the nose from rising with go around thrust. To go from full aft trim to something like say 7 units takes about 14 seconds, which feels like a long time. It takes several seconds of trimming to actually feel the elevator start to have a reasonable amount authority and the amount of
required force to reduce.