Postwork can be a dirty word when a software company uses it to sell rendering software programs and does not admit or tell it's buyers the images posted around it could not have been created in the program all by itself. It's called false advertisement or misleading the consumer.

Saying there is no Postwork in an image can be impressive and it also makes clear that the image was created in "The one" program and that single program coupled with the artist's talents were all that were involved in the creation of the image or images. Other than that Postwork is fine. Some people try to see how good they can make renders without the use of it and take pride in their ability.

My opinion, :)