PROGLIB=YES directs CA XCOM to invoke IEBCOPY with the COPYGRP function to copy the dataset before transferring it to the remote PDSE.
Due to the nature of PDSE program library datasets, this preprocessing is required for CA XCOM to transfer this type of library. CA XCOM will not copy the dataset first if PROGLIB=NO is specified. PROGLIB=YES is only necessary if the TARGET dataset is a PDSE program library. SOURCE PDSE's can be transferred using PROGLIB=NO. Specifying PROGLIB=YES when transferring a SOURCE PDSE will still be successful, but will affect the performance.