i'd say experience. he knows what hes doing. Also he's fortunate it's thin paper. I remember my first job was as a helper on an old Roland 900 which printed solid cardboard up to 1200gr/m². I had to do non stops every 6 minutes. Each pallet only had about 800 sheets. All the while preparing all pallets, mixing ink, checking ink, and helping the input of another Roland 800. The sheets were absolutely hell. On some pallets the left side was up to 30 cm higher than the right side or vice versa. they were full of thick black stripes that absolutely wrecked the rubbers.
KBA is awful. This is during the 10 minutes of runtime for the day. Pure garbage. They suck. Never buy one if you're serious about production. I can't stress this enough.
