Soliciting comments on Torbirdy

Greeting folks:

Like many I use TOR heavily. About 3-4 months ago I discovered the Mozilla Add-on TorBirdy. I route all my outgoing smtp mail now via an authenticated .onion address (starttls, port 587). I am writing this to accomplish two goals. The first goal is a question. Despite the fact that am routing my outgoing mail through a .onion does the fact that I am using Torbirdy route all my mail out through the Tor circuit anyway? Amy I needlessly duplicating my efforts? Also, I am fascinated with Torbirdy. I am in addition soliciting comments from anyone who would care to talk. Thank you ...