~Common to the Craftsman ~
...period, a double door was often found between the kitchen and the formal dining room. The home that this beautiful double door came from dates back to the 1920's.
The formal side that most guests would see when visiting is oak. The informal side facing the kitchen is made of pine. The double swing hinge is a tricky thing to "tweak." In this case a new floor was added on the kitchen side requiring that the door be "shortened" 3/4".
It would have been much easier to take it off the top of the door, but then the raised panel's would have been ill proportioned. This discrete correction makes the door look as if it had always been this way.