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Boeing did not spend millions on MCAS to "make it feel" like the 737 NG. They spent millions on the MCAS system to compensate for the engine redesign. Then engines weren't "just slightly larger" and just a few inches further forward. They're an entirely different design with different performance. Boeing was avoiding having to recertify the airframe and push the cost of training pilots onto all their customers. That desire to cut or avoid costs proved deadly - twice.

As for "MCAS was implemented to prevent the need for extra training, not to make an unstable aircraft"...???...No one said that. It's the opposite, the aircraft was unstable in certain flight configurations and the MCAS system was designed to mitigate that.

The newer engines are more powerful than their predecessors and since they have a larger diameter, not only did Boeing move them forward, they moved them higher. The new power and location created the potential for the nose to pitch up during flight. If the nose was already high, the plane risked stalling. When the sensor detected the nose being too high, it automatically pushed the nose down.

The fact MCAS would activate at all is a clear indicator that the plane is NOT stable in all flight profiles. The pilots didn't push the nose up into the stall, the out of tolerance center of lift vs the center of gravity did. That's the very definition of unstable, right there in the FAR.

If you read my previous posts to you, you’ll see I’m well aware of the differences between the NG and the MAX, including the measurements of the fan diameter and engine relocation from CFM 56’s to the CFM LEAPs.

Yes, the MCAS was installed to make the MAX plane behave, i.e. feel, like the NG.

All modern aircraft pitch up with increasing throttle. All of them. The 737 NG and A320 included. This is not unique to the 737 MAX.

Are you calling all modern airliners unstable, or just singling out the MAX?

I repeat, all modern airliners pitch up with increased throttle. Yet they all have their CoG ahead of their CoL, so they are considered stable, including the MAX.

And yes, the LEAP’s are more powerful than the CFM56’s, so yes the pitch up will be greater. But again, this doesn’t make the plane “unstable” like your F-16 comment.

The main problem with the MCAS was that for some insane reason, Boeing decided to allow a single sensor failure cause the plane to fly itself right into the ground. (This is no longer the case.) I have already written about the other issues with the MCAS, which have also been resolved.