Yeah absolutely but if you are running a simulation/test would you deliberately inject some random sensor failure if you are doing your tests for something else

Yeah absolutely but if you are running a simulation/test would you deliberately inject some random sensor failure if you are doing your tests for something else? It is not clear what they were testing - perhaps they were indeed testing the MCAS system with sensor failures, but if so I probably wouldn't have expected such a surprised resction from them. It seemed like it was totally unexpected and unexplained, which is not a reaction I would expect if they were testing this.