To help you understand which recommendation block(s) is performing better, we have now enabled click through rates for recommendation blocks, and other links used in email templates. You can find the send and click stats per link/ block on the click heat map report within the ‘Engagement’ tab of the Email Studio.
This will help you A/B test similar blocks across multiple templates. For example, if you have a 30-day look back period for a “customers who bought X also bought Y” recommendation block in template A and a 90-day look back period for a similar recommendation block in template B, you can test which of the 2 recommendation blocks and hence which of the 2 look back periods had a higher click through rate.