My training required shouting in all of the drills. The reasoning that was given was that it was required to make sure any and all bystanders and recording devices heard you clearly so there would be evidence that you followed procedure and that they did not follow commands.
Perhaps this is now outdated with the introduction of body cams but I would bet it is still taught that way.
Perhaps this is now outdated with the introduction of body cams but I would bet it is still taught that way.