Many of us are using InDesign to output digital formats as well as print. The inability to convert spreads in large documents that involve things like complex tiered master page assignments and interactive elements between print friendly spreads and digital friendly tabloid page layouts is a major pain. A non-destructive way to move back and forth would dramatically simplify digital exports, and ensure a clean single large page digital presentation to the end user without hassling with software adjustments to view spreads correctly.