Originally Posted by
kaszeta
It was noticeably more efficient than my typical boarding experience, despite the level of carry-on baggage generally being higher than a lot of my US domestic flights; those overhead bins were packed (primarily since due to high pilferage, the airlines requested that all valuable items come onboard)
That would be the easiest way to speed up loading/unloading - get rid of those big carry-on bags.
Furthermore, airstairs are typically narrow with little or no room to overtake when carrying luggage - so one person moving very slowly will delay a long queue of people
Passing people on stairs while carrying luggage?