Practically none of the Mentor customers, nor the wider electronics industry are in the business of producing single PCBs. Companies develop and sell products containing multiple boards connected together via cables and backplanes to form a system. When looking at the various issues often faced with multi-board system design Mentor has identified three capabilities that are considered absolutely key:
xSD extends the scope of the Mentor PCB tools into the multi-board systems arena but are these the only key challenges?
You have forgotten key challenge: Convincing Management to invest in yet another tool. Any ROI on obscure system definition time is quiet a challenge. :-)