Dave #12,
Agreed, the force characteristic of the trim wheel might not differ that much. However, the differences in the ‘not so similar’ aerodynamics (why was MCAS required) could result in the Max reaching the same value of force with a lower stab displacement, thus the inference is that the Max would have higher forces at the limit of the screw jack. Even a small difference could have a much greater effect if the elevator feel system was active due to AoA error.
Ignoring AoA (and MCAS,
it must not fail the same way again), then the assumption in the trim runaway drill that there would be some elevator available to aid recovery from trim runaway - nose up ‘yo-yo’, could be severely challenged. (see FAA investigates drill)
Crazy (and surprising) things happen every day,
Even crazier - the 737 NG could differ in these characteristics from previous variants.
The more that is established from the investigations and ‘fall-out’ from these accidents, the more we don’t know. So who knew, who did not know, who needs to know, now.
In reality, a simple view could be that the sim might not have triggered the 4x force from the elevator feel shift at the same time as the MCAS induced trim movement, because MCAS was not expected to fail.
Trim runaway
and AoA fail might also be an excluded failure in certification due to extreme improbability.