Certification
The certification requirements provide a standard for the design of aircraft; a comparative measurement based on a minimum time; aircraft configuration, seats, flight attendants, number of (operating) doors, a range of passengers, and conducted at night.
The use of these requirements for operational approval can overlook the essential need for crews’ understanding of procedures and priorities - ability to adapt to each unique, surprising situations, which will not be the same as used for certification. i.e. passengers will not behave as demonstrated in certification; in the real world crews have to intervene, encourage, etc.
Operational assessments (nor accident investigations) should not be judged by timing, which is often detrimental to necessary understanding required for safe operation; safety first, can procedures be better applied, what more can be learnt.
“There's nowt so queer as folk”; regulators, operational assessors, investigators, downwards; poor old cabin crew at the bottom layer facing reality, have to manage an ‘unmanageable’ situation involving real passengers.
Work as done is never as imagined; regulations have limited, constrained imagination.
The outcome of this event was safe; well done the crew. What can others in industry learn from this event, how, and then apply this without regulatory intervention.