The trick would be getting the screen flat... the weighted bar provides even tension across the width of the screen... that may be difficult to replicate without a fairly complicated attachment to whatever you attach it to (I'd expect single point attachment to have waves due to flex in the bar). Also, not clear if the spring/retension mechanism will operate effectively to provide the anchor at the bottom... and if not, the attachment to the screen at the bar may not support the weight of the case (which is much greater than the weight of the bar). Only way to find out is to try it, but I'd expect there is a good chance you'd be wasting your money.
"A wide screen just makes a bad film twice as bad. "
I wonder what he'd think about 3D IMAX?