RT and Clay mode

Hmmmm.. interesting !
but will be hard for one reason :

RT reflects the scene "as it is"... of course i can parse materials just before launching RT and replace by white material, but when can i restore the original ones ? RT is independant, and user can immediatly work on the scene, while RT is running. so i must in this case restore the original materials... and RT will reflect this change immediatly...
Kind of jawbreaker

you're right, SR parses all the scene materials and affect every material one by one via recursive algorithm.