The second part of your question seems to relate to the BPX role that SAP is trying to promote. I totally agree that a composite developer should engage in process modeling in order to better translate the business process requirement into a technical language that would be implement-able with the MDD tools. Process modeling can be expressed with a variety of notation languages like BPMN or ePC. There's no way in NetWeaver to directly translate such notations into SAP Visual Composer, Guided Procedures or XI for example. It's a manual translation effort requiring a lot of iterations, and for those reasons, somebody has to do such translation. That translation between business requirements and technical implementations in a world of composition would be the responsibility of a business process expert (www.bpx.sap.com) or the one you called composite developer.
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