Depot Repair Loaner Process

Can someone please explain the loaner process for Depot Repair?  The white paper describing the loaner repair type (ID: 412088.1) seems to have a conflict.  In the overview (for “Loaner”), it says “This Repair Type requires a Sales Order to ship the loaner item to the customer and to create an invoice, and an RMA order to track the return of the loaner item.”  Then, in the setups, it goes on to detail setting up the loaner repair type with both a ship line and a return line.  If the loaner repair type requires a Sales Order, then why is there a ship line in the setup for the RMA?