Reinvention for the sake of reinvention is fundamentally a bad idea. Re-engineering the print path was a long-overdue effort, where we revisited a lot of current components to see how we can wring out known problems and insert significant improvements. Using a subset of WPF in the spool file format was key to improving fidelity and enabling advanced graphic features such as transparencies and gradients. Resource reuse and ZIP were key to reducing spool file sizes. Taking into account the limitations with embedding the format in a device enabled us to also create a device consumable PDL. So, yes, many components were "reinvented". WPF was a reinvention of GDI and XPS was a reinvention of the EMF spool file format and a PDL (PDLs exist such as PCL and Postscript). The XPSDrv filter pipeline was a reinvention of the GDI print driver model. Reinvention is progress. The key point here is that the customer will realize value through the effort.