Interesting. A viewpoint of the maker of 3D movies.
My father was a 3d photographer: Leica-3d-adapter, Verascope, Viewmaster, etc. He never adapted the red/green technic, he worked with either double slideviewers or a polafilter-projector.
The stereo effect was clearly visible, also for the family. But it stayed in the state of an effect, a demonstration of an optical illusion.
I have always suspected the difficult height standardization of the 2 slides as the cause of (light) headaches. But the argument in the article is, that it is a structural problem.
Jan