Not to crack open a very annoying semantic argument again but our vision of the 3D world is just a 2D plane so having "3D" - by which I guess you mean perceptio

Not to crack open a very annoying semantic argument again but our vision of the 3D world is just a 2D plane so having "3D" - by which I guess you mean perception of depth through parallax - would do little to ease visualization of 4D surfaces.