Theoretically this could work like a charm. Somehow I think it would also work in a practice.

Additional thinkering about this: So the freeze would happen when you hit "RENDER". So it would render it from the source to the latest device in the Mix channel. Notice that you could change the volume and the pan or any knob/button on the SSL mixer WITHOUT a need to re-render anything. (as these parameters come after the chain). But anyway, it would be an uber-cool optimizing method and make our setups say thank you imo.
