This is categorically untrue.Spitfire libraries are processed. I believe they EQ their libraries, use compression per dynamic layer then bounce it and put it into Kontakt and you crossfade between processed layers. The clues are there in the samples. They sound good out of the box, but they take control away from you and with that come all the problems that these libraries have and that people have complained about.
Unless we publicize the specific processing by an artist - eg: HZ percussion -
Our orchestral libraries recorded at Air are not “post processed” in the way alleged above.