So they don't advertise real life emergencies in advance then? I am still of the view that the announcement is made and then you are to proceed to the muster point. If not then why would there be staff stationed along the route? It is not a "drill" if everyone turns up long before the event, it would just be an explanation of a procedure. Surely the idea of it is to simulate an emergency.
Generally, the muster drill is taken in simple instructions:
An announcement is normally made to passengers, informing them that a mandatory muster drill will begin shortly.
Then, another announcement is made, informing crew and passengers, that the "general emergency alarm" is about to be sounded for exercise purposes only.
After the alarm has been sounded, passengers are told to then make their way to their muster station.
Upon reaching their muster station, passengers are informed of the use of life jackets, lifeboats, etc.
A final signal is made, informing that the muster drill is concluded.