[INFO] TTX Ver. 3.0 Be carefull setting the broadcast value as Bcc.

[mdbennet]

I am using TTX Ver. 3.0 and have used the broadcast= in the config file as a Bcc. 
If you are using the groups module TTX emails every transaction to everyone in the group.
The comma separated email address list set in the broadcast= will receive duplicate emails sent to all users in the group.

This is a great testing tool to check email delivery, but if you have 5 users in a particular group you will be delivering 5 emails for every transaction to each email address in the broadcast list, and they will soon get pounded with unwanted duplicate emails.