Interesting points. The fact that ATT does not work is either an oversight or shoddy programming. All it requires is to stop the part of the IRS software which updates the nav solution and clear down a few validity flags.
Some years ago I was involved in producing an engine seize malfunction for a military sim. There was a blood curdling graunch and the motion nearly tore itself out of the floor. Had the occupants not been strapped in and wearing bonedomes, there would have been injuries. We were rather pleased with ourselves. Off to site and the mod was installed and submitted to the customer for approval. "Do you like it" says us. "Oh yes indeed" says the customer. "Is it realistic" asks us. "Dunno, never happened in real life" Says the customer.
Basically, there are two ways of getting the information to simulate something -
1/. A mass of instrumentation is installed in the aircraft then you go flying and actually carry out the event.
2/. You ask lots of people what it feels like. You then produce something based on an average of the answers. This is then submitted to customers and is tuned until they are happy.
In the case of an engine catastrophic failure, no one seems keen to let us use method one, and method two is not good because of it's subjective nature. What usually happens is that you can please one pilot but another is less happy. Everyone tends to have a slightly different slant on what should happen.
Still it's fun trying
