Not a real solution, but a workaround we use:
If you run a nvidia-setup, have a look into shadowplay. It’s a screen-grab, that captures directly from the framebuffer (thus in smooth framerate). Prepare a matinee camera track or whatever and trigger the shadowplay recording when you trigger the camera track (you can send system-commands from inside the engine). Doing this, you can capture videos from your runtime without the need for going inside matinee.
We did this for a couple of Viz-projects so far.
But yes…i’d welcome that feature as well