How to Run Advantage+ & Performance Max Without Losing Control
For Marketers Tired of Watching “Smart” Campaigns Do Dumb Things
In yesterday’s free article, we made one thing clear:
Automation doesn’t create volatility.
It accelerates whatever system you built.
This paid piece assumes you accept that premise — and answers the next, more useful question:
How do you design experiments that work with Advantage+ and Performance Max instead of being punished by them?
This is not about “testing more”.
It’s about testing differently — in a way automated systems can actually learn from.
Why Most Tests Fail on Advantage+ & PMax
Let’s start with the uncomfortable truth.
Most “experiments” on automated platforms fail because they violate basic system rules.
Common failure patterns:
Multiple variables change at once
Budgets fluctuate mid-test
Audiences overlap invisibly
Optimisation goals drift during learning
Results are read too early
Automation doesn’t break here.
Causality does.
Advantage+ and PMax are not campaign types.
They are allocation engines.
If you don’t constrain what they’re allowed to learn, they learn the wrong thing very efficiently.
The Core Reframe: You Don’t Test Ads — You Test Allocation Logic
Manual platforms let you test inputs.
Automated platforms test where marginal dollars go.
That means your experiment unit changes.
You are no longer testing:
“Creative A vs B”
“Audience X vs Y”
You are testing:
Which signals deserve more budget
Which constraints protect quality while scaling
This is why traditional A/B logic breaks — and why volatility spikes when teams “just test”.



