to add, i've seen other drivers that are "runner/gunners" with their bulkhead door open while driving & other "shortcuts" just to shove these packages out of their vehicles ASAP since we're not "hourly" employees. Basically did a "check ride" to see just how they're smoking their routes so fast...
one route, when following the methods, should have been done by 1600-1700, but this one driver can smoke it by 1400.
When I was riding along and observing his "methods" he forgot to use the parking brake & left the vehicle in "D"... rolls the vehicle ~3x during the day

because at some stops, he'll just leave the keys in the ignition & keeps it idling since he can "run" to-fro the vehicle to the porch in under a minute. that was the only concern i had to relay to the driver-start using your parking brake at every stop & just make it a part of his routine.