Purism goes beyond just doing post work, it also means not using any imported meshes made from other apps too. For Bryce it would be making everything from within Bryce. I am not a purist because I make my models in other apps and texture map them in Bryce. Don't really care how other folks make their pictures but the Purist vs Importers debate always seems to come up on the contests. Think that the genre stuff is good because pictures can get more views. The bad side is that people that have large galleries have to do a lot of work.