The MCAS system is probably not the best example here because it doesn’t take expert knowledge on MCAS to catch lack of redundancy and poor documentation in the design of a system so critical. This one of the reasons patterns, processes and standards exist. I did this for a living and consulted for many companies in processes my team had no domain experience with, still we were able to catch process gaps. MCAS IMO was a flaw easy to flag for any competent auditor.