general question regarding flexibility of unity3d rendering

hi - i'm about to start a new project - and i'm considering the unity3d framework. (my other option is to code the whole thing from scratch using opengl.)

the decision will hinge on how flexible unity3d's rendering framework is: will i be able to do the "tricks" i need to.

the primary "trick" i need is this: render a very simple scene in the "style" of deferred rendering - but before lighting is computed, i need to blur some areas of the screen-normal-map - to eliminate sharp edges between geometry.

possible?

followup question: can i do this using unity3d's built-in deferred rendering system, or will i have to create a poor-man's version?