Allow content & subject line testing for automation emails

Allow content & subject line testing for automation emails

Purpose
Email is the gold standard for web marketing, because it is so easy to measure results.  Any email marketing expert will tell you to test & improve emails continually.
 
Requirements

Ability to test 3-5 emails, including subject lines & content

Results based on;
-> subject lines
-> click thrus

Independent reports for each variation, winner automatically used for future mails sent in automation.