Do rotors always need cleaning?

[thebluedog]

I am replacing my brakes and rotors. I purchased Textar high carbon rotors and the packaging states that they are installation ready and require NO CLEANING. It seems that every rotor replacement job, including the Bentley manual states to clean the rotors with brake cleaner. So, is it possible to skip that step on these rotors. My Indy shop purchased these thru their supplier and they basically said to spray them with brake cleaner and wipe them down. It won't hurt to clean them with brake cleaner but I'm just curious to know if cleaning them is even necessary since these indicate "installation ready". It would be nice not to have bother cleaning them since I am doing front and rear.