In retrospect, I'm sure you've examined all the information you received from pilots, on simulators and so on. Was there anything that talked about what you've identified as probably the crucial factor, in other words, changing the technology, the MCAS system, and what that did to the safety of the aircraft as a whole, in other words, the interaction with the existing aircraft? If you look back, have you seen anything that might have led you to have a really important concern and to issue yet another concern paper?
