Old not bold and paxboy:
You have both encapsulated the problems/background involved in this whole safety briefing situation.
Like you ONB, I have been flying both at the front and the back, since the days of the DC-3, and have been subjected to various 'unforseen circumstances' whilst flying. The reaction of most of the passengers in these cases was not reassuring!
As a former employee of a manufacturer, and having taken part in one of the evacuations required to gain certification, I would endorse your comments.
The advent of floor strip lighting came about following the Airtours accident at MAN in 1985, precisely because so many of the passengers could not find their way to exits, partly because of the smoke, but also because they were not sure where they were. Several of the cabin crew died in this fire, and were thus unable to help the passengers, so the very reason for their existence was immediately negated. Videos are better, (though sadly not the VS one imho), but to have some wannabee comedian doing the briefing is definitely not the way forward.
One step forward has been to deny seats to those unwilling or unable to operate the emergency exits, and to brief those willing to operate the equipment. A follow-up random questioning of the pax on the other procedures eg "Do you know where your nearest exit is?/Would you inflate your lifejacket before leaving the aircraft?/Where will the oxygen masks appear from etc?" would probably provoke aggression amongst some of those who answered incorrectly, such is the world we live in.
I wonder, in the case of the SW guy, how many pax would have taken out lawsuits against him/them, on the basis that the briefing was not conducted in the normal fashion, had the worst happened?