It is not necessary, for example, to wait at round-abouts until every last vehicle in existence disappears from view. I sat this lunchtime behind a driver who did just that. For five minutes the queue grew all the way up Dublin St while the driver – clearly flummoxed by all the traffic – waited until the tumble weeds rolled by before moving on.
Others take the slow down message too far. Holding up dozens of people needing to get from A to B while ambling along at 25km/h with no consideration for those accumulating in numbers behind is not a very Chrismassy thing to do.
That said let's applaud the many examples I see daily of considerate driving - letting people into the queue one car at a time (merge like a zip folks), and exchanges of polite gestures of thanks and occasional big friendly smiles.
Things will possibly settle down after Christmas. Meantime if you have to drive over the next few days it's probably best to leave 10 minutes earlier than you would normally. It's chaos out there.