My compositional skills using the twin-lens camera could have used a little honing. I know that in the back of my mind I planned on turning the square compositions that the camera took into rectangular ones. During a workshop I took in Asilomar, Henry Gilpin (a Monterey County photographer) said that that was his procedure.
The only problem was trying to visualize in advance whether or not your final photo was going to be horizontal or vertical. Maybe it would have been better to just stick with the square, like so.