Hi Joe
I have a 3 stop reverse grad but have rarely used it. I just haven't found the need for it compared to ordinary GND's. I believe that Reverse grads are meant to cover the situation where the sun is just above the horizon. In this situation, you can have very bright direct sunlight in shot (unless it is filtered by cloud) but 3 stops of filtering with a reverse grad will not stop it blowing out anyway.
I don't usually shoot sunrises or sunsets when the sun is above the horizon unless there are clouds just above the horizon. I thnk this shot may have been done with my reverse grad.
Dave