Split the postfix role into a role for mail.a.o and the clients
The role for the clients is named postfix_null (per [1]) and it's much simpler and cleaner than the postfix role. I hope can cleanup the postfix role at a later date.
[1] http://www.postfix.org/STANDARD_CONFIGURATION_README.html#null_client
Already deployed
Edited by Kristian Klausen