Never thought about 3D films as it related to human vision, but this makes a lot of sense. I do feel very strained watching a 3D film.
Walter Murch, Oscar-winning film editor:
The biggest problem with 3D, though, is the “convergence/focus” issue. A couple of the other issues — darkness and “smallness” — are at least theoretically solvable. But the deeper problem is that the audience must focus their eyes at the plane of the screen — say it is 80 feet away. This is constant no matter what.
But their eyes must converge at perhaps 10 feet away, then 60 feet, then 120 feet, and so on, depending on what the illusion is. So 3D films require us to focus at one distance and converge at another. And 600 million years of evolution has never presented this problem before. All living things with eyes have always focussed and converged at the same point.
Read: Why 3D doesn’t work and never will. Case closed. – Roger Ebert’s Journal.