Hey all, following up on this, I emailed Stephanie, a Marketo architect and got a very detailed response from her. Sharing it here in hopes that it will help anyone who has the same confusion as I did: "Hi Dylan, Apologies - I just noticed your email now. Setting up A/B testing directly on the email asset will only work for trigger campaign as you well aware for challenger email. Marketo sets this up and ensures that ultimately each version will be proportionately sent out to a percentage of people considering that it is a trigger campaign, which means that you do not know how many people will go through the program at the end of the day. An A/B test can only work for Email Program. This does not work for any other channel. Normally with A/B testing, you are looking at which email performs the best and from there you can start implementing your own best practice of an email. You also want to ensure that you can get the right type of reporting for the entire marketing program. This means the build of the program is important to provide you with the right ROI reporting. The challenger email reduces the complexity for trigger campaigns, so you can focus on building a program for the reporting that you need. Another way to do A/B testing is by using random sample flow step for batch campaign that is not an email program. Happy to go through this with you in depth if needed." ... View more

Hi Veronica, You are right. I realised that the smart list did not contain triggers, which explains why the Champion/Challener did not work. Do you happen to have a link to a guide on how to create a nested email program with A/B testing? I have been exploring the different options available in Marketo to no avail. ... View more

Hi Ronen, Thanks for your response! Do you have a link to a guide on how to create an A/B test through an Email program? I have been exploring the different options available in Marketo to no avail. ... View more