Bill Tindall, E.Tn.
For fitting doors I take guidance from the Bunn article in FWW July/August 1994 Vol 107 p67. Mr. Bunn worked for Moser furniture company where he fit doors. This kind of source I find reliable. I depart some, setting my hinges in about 40% of the barrel diameter and I use a smaller reveal between adjacent doors.
For the door for the upper corner cupboard I tried something different. Bunn's approach is to make a door too big and shave stuff off until it fits the opening which often is not perfectly square. The left opening was ever so slightly out of square and the frame as it naturally came together was ever so slightly out of square in the opposite manner. The sum of these compounding errors would result in more than 1/16" correction on the door elements.
I am going to see if I can get a head start on the fit by gluing the door in the opening and thereby fixing two of its sides by whatever shape the opening is. Stay tuned to see if this head start really helped.