I am using ArcMap 10.4.1.
I am still reviewing the basics of map projections and came across the concept of planar projections not fully touching at edges, due to distortion, if for example, the globe was projected using a planar stereographic type Planar Projection. However, I it seems to me that none of the State Plane zones would likely "stich" together seamlessly at the edges either. But I also thought one of the advantages of the State Plane System was that it offered continuity between large areas that are projected. So I have to ask, do the State Plane projections between states touch seamlessly at edges, or can one expect a distorted miss-alignment along zone edges ?