I think 3 minutes is a little on the long side, I'm now 75 and still could tie on a hand brake is about a minute or so . Crews don't have to climb to the top of the car anymore. Engine hand brakes may take a little longer.
However how would like to show up for work in really COLD WEATHER and the first thing you have to do is tie on a hundred hand brakes. After the train line is charged , a brake application applied, release the 100 hand brakes you just tied on.. .
I don't know what the answer is..... More engines for braking power?, retainers.? I wonder how many engines it would take to hold this train with either the independent or dynamic with the train brakes released.
I believe CN & CP do not use the metric system for mileage or speed. There was some reference to excessive speed at 32 kilometres per hour, That is only about 18 miles per hour.