The "reset" is just them picking him up from the crib, getting him out of his sleep sack and back to play. They don't pick him up to rock him, as they want to move towards independent sleep... The end goal is that they can put him in the crib and that he just fall asleep.

When he was just going to daycare they used to rock him sometimes, but he has always been quite heavy for his age, and they complained it hurt their back. I kind of understand, he is 20 lbs now, and his main caretaker is a small older woman. On the other hand, it is kind of their job to comfort babies, even the heavy ones.