I think there's a research opportunity for someone that can dig through the original Dumont Laboratories papers in the Library of Congress on the "Duscopic" television prototypes.
I think the Duoscopic tv was originally developed for another purpose: 3d television.
I've not been able to find a link to it (perhaps someone at the Museum will recall seeing it), but a few years ago I ran into a publicity photo on a website from Dumont showing a 3d setup they had developed for the military. The photo showed someone in uniform sitting in front of a monitor and the monitor clearly showed two "side by side" 3d images, a format commonly used for printed 3d materials in scientific and military work for many years. (The images could be viewed in 3d by crossing one's eyes or using an cardboard viewer placed over the two images.)
The dating of the Duoscopic tv is curious - "Bwana Devil" came out in late 1952 and created a sensation with audiences and exhibitors, kicking off the 3d craze. The use of two monitor with polarized lenses mimics the same method used for 3d theatrical films.
By 1954, when the Duoscopic was first seen in these publicity photos, the 3d fad had started to fade. I have to wonder if Dumont started researching 3d tv, then found it impractical (difficulty synchronizing the two signals?) or simply waited a little too long to announce it, with the 3d fad passing, and "rejiggered" the technology as a way for two people to watch two different television programs.
If they were pursuing 3d television research, and 3d stayed popular, it might have given them leverage to get additional channels in major markets - the system would have required tv stations transmitting the same program on two channels or some wider bandwidth solution to transmit left-right image pairs. Dumont could have argued for two uhf slots or a vhf and uhf slot for 3d programming. In other words, they might have seen it as a way to get the FCC to push for more channels and opening up of the uhf band to television.