Chiasm in Philemon?

Having just finished my read through of Genesis (I know you can’t tell by looking at my posts), I decided to camp out in the little book of Philemon.  After reading it through a couple of times, I have begun to question: Has Paul built this letter into a chiasm?  Here is what I’ve found (if in fact it is actually in the text):

A.  1:1-3 and 23-25 — Listing and mention of fellow laborers and prisoners.  Repetitions: “colaborers”, “prisoners”

B.  1:4-7 and 20-22 — Philemon’s service to the church.  Repetitions: “prayer”, “hearts…refreshed through you”, abundance in Christ (6) and abundance of response (21)

C.  1:8-9 and 17-19 — The basis of Paul’s appeal.  Parrallels: partner (17) and “the basis of love” (9), “doing what is proper” (8) and “charge what he owes to me…I could also mention that you owe me your very self”

D.  1:10-12 and 15-16 — Familial relationship with Onisimus.  Repetitions/Parallels: Paul to Onesimus (10) and Philemon to Onesimus brother (16), “formerly useless to you” (11) and “no longer as a slave” (16)

E.  1:13 and 14  — Center of the Chiasm: Paul’s appeal for Onesimus’ help by Philemon’s willing permission. 

Repetitions/Parallels that Don’t Exactly Fit:

• Paul’s Prayer (6) and his writing (19) don’t quite fit in the form
• “Confidence” in v. 8 and 21
• “our fellow soldier” seems only to find echo in the “command” mentioned in v. 8

If indeed Paul has fashioned this letter “in his own hand” (19) so that, notwithstanding the misfits above, his appeal would fall in the center of his book, what should we pick up from that?  My guess is that (assuming chiasm), Paul’s intent is in highlighting this portion of his multifaceted, often dubious, and possibly manipulative letter to Philemon. 

Further Study: What devices does Paul use to convince Philemon?  Should Philemon be read in concert with Colossians or not?  Do the repetitions/parallels that don’t fit portent to a different strategy?