I am just on my first stereo project.
I am reviewing our shots everyday with RV and thats where the idea came from to set floating windows in RV and either export the data (if it is animated how many pixels wide and on which eye it needs to be ) or render a mask in RV !?
It is just a crop in the end so reviewing that in almost realtime and being able to change that sounds good to me.
It is nothing urgent but it would fit in the toolset in my opinion.
Cheers
Johannes