Bart Ehrmann recently commented that onl 7 of 13 letters of the NT attributed to Paul were actually written by him. Ehrman bases this on the idea that Paul "wrote in short pointed sentences." Philemon is the fourth letter attributed to Paul that I've diagrammed and through my personal study I say Ehrmann is full of it! This little book is NOT in any meaningful way different from 1 or 2 Thess or Galatians. If there are differences there are better explanations than "forgery" (as Ehrmann calls them).
I have attached a zip file of a Reed/Kellogg Greek sentence diagram of Paul's letter to Philemon.
Terry Cook
sDg
0880.Philemon.zip