Sully Sullenberger's opinions is that the MCAS failure is not a "normal" trim runaway failure:
> These emergencies did not present as a classic runaway stabilizer problem, but initially as ambiguous unreliable airspeed and altitude situations, masking MCAS.
> These emergencies did not present as a classic runaway stabilizer problem, but initially as ambiguous unreliable airspeed and altitude situations, masking MCAS.
http://www.sullysullenberger.com/my-letter-to-the-editor-of-...
He bases that opinion on having flown the scenario in a professional full motion simulator (explained in the rest of his letter).
What's your response to that?