Catching bounced mail with "External Address" option

[joelcollinsdc]

According to the civicrm documentation, there are 3 methods for incoming mail

• Sub addressing
• Catch All Account
• External Address "if nether of the above 2 work"

I am attempting to use an external address (Exchange) AND our mail system does not support subaddressing.  Will I be able to configure bounce processing with an external address that does not support subaddressing?  I think the documentation unclear here as to the requirements of the external address option.

I'd love to see sample configurations for bounce processing using each of the 3 options listed instead of having 1 section with a description of the fields for configuring mail accounts.