Google has published a help page detailing a new asset-testing experiment for Performance Max called “Asset testing for retailers“.
Instead of running two campaigns, this test tests a specific PMAX feature, in this case it splits traffic within a single campaign, comparing a control group (feed-only) with a treatment group (with added assets).
Advertisers can track results in the Experiment report and apply or discard changes after testing.
Get all the details about the new help page here: About Performance Max optimization experiments: Asset testing.