Thanks IMEff for a detailed point by point reply. I question two items:

Personally I would think in a true emergency, actions speak much louder than words. It would be instinctive to exit the aircraft. Your job, sitting by the exit, would be to assist people out of the plane.

Of course it's instinctive. It's also instinctive to enter the plane through the door when boarding. A key problem in an emergency is how to move people out quickly and smoothly.

Bahasa Indonesia is a national language that most people don't learn until age 3 or older, when they go to school. In an emergency (e.g., a bus accident), most if not all Indonesians prefer to speak their mother tongue: Javanese, Balinese, Minang, etc. I am fluent in none of those.

The larger issue for the airline is how to train attendants to remain composed and give clear instructions in a language that is probably not "instinctive" for any of them.

Regarding the comment about rafts being "extensively tested", I have no doubt that is true -- component by component. Rafts are probably tested in water, but I doubt any manufacturer sits a plane in water and determines whether the slides pop out under such conditions. It's probably not feasible to have a *complete* systems test in realistic circumstances ... which may be true for safety features in other walks of life. We take it for granted.