Following are the benefits.
Reduces optionality that results in more specific messages
Uncovers hidden assumptions about application boundaries
Facilities defining clear, fine-grained, conformance claims
The HL7 V3 specification contains the XSDs for Interactions which can be used to construct the composite HL7 V3 message. This composite message then can be transmitted between the systems. The V3 Specification says that a system can claim for V3 conformance based on the Application Role it will play in a particular domain. The system playing the Application Role will recognize the Trigger Events, the message types and the data content of these messages. Thus a system whose sole responsibility is to exchange the V3 data between systems reliably should claim conformance for the Application Roles defined under Transmission Infrastructure Domain.