Caboose were eliminated in the 80s. So was the 5-man crew. With thru trains going from A to B with no stops, a 2-man crew is the norm. The conductor is the boss, not the engineer. He rides up front in the cab. Locals and other trains that have work to do along the way - typical for regionals and short lines - will have a 3 or 4 man crew. some one needs to be on the ground throwing switches.
Thanks for the education.