Doorway to DeKooning

I was told that Willem DeKooning often put a door in his paintings. So, I went to check it out on "Excavation" in the Modern Wing. Sure enough, there is a doorway with the door cracked and opening to the inside. Check it out. It is buried in the abstract elements in the central lower part of the painting. Apparently he did this on many paintings. Was this a mental tool or escape route if he got "stuck"? Was it simply a visual motif that he was carrying through during that period of his career? No one seems to know. . . Truth stranger than fiction.