Google Ads: Answers to the Most Technical Questions (Performance Max, Tracking, Cross‑sell & More)

Every week Pierre‑Baptiste (Céos) receives dozens of questions about Google Ads — from strategy to highly technical topics. This article distills his recent FAQ video into a practical, step‑by‑step guide you can use right away. We cover campaign choice (Search vs Shopping vs Performance Max), when to use Performance Max feed‑only, how to handle audiences and tracking, cross‑sell measurement, and the new performance‑by‑channel insights in Google Ads.

Table of Contents

• Quick summary: what you’ll learn
• 1. Which campaign should you start with?
• 2. Performance Max feed‑only vs classic Google Shopping
• 3. Feed‑only vs full‑asset PMax: brands and long term value
• 4. Asset groups inside PMax — should you split product groups?
• 5. Audience signals — should you upload customer lists at launch?
• 6. Tracking vs ROAS target — don’t confuse them
• 7. Using AI / ChatGPT to write product titles and descriptions
• 8. Cross‑sell tracking: what you can and cannot know
• 9. New: Performance by Channel in Performance Max
• Practical checklist to act on today
• Conclusion
• FAQ

Quick summary: what you’ll learn

• How to choose your first campaign type depending on business goal (e‑commerce vs leads).
• Why Performance Max (PMax) feed‑only is often the best long‑term option for e‑commerce.
• When to use full‑asset PMax versus feed‑only, and how to structure asset groups.
• How to use audience signals and when to upload customer lists.
• Difference between tracking and bid strategy (ROAS target).
• How cross‑sell tracking works — and its limitations.
• How to read the new Performance by Channel report in PMax.

1. Which campaign should you start with?

First, decide whether you want to generate leads or sell products. That decision drives the initial campaign choice:

• Leads: Start with Search. You control keywords, ad copy and landing pages — ideal for lead intent.
• E‑commerce: Start with Shopping (or Performance Max tuned for shopping). Shopping ads show price and product info upfront and usually deliver the best ROI for product sales.

2. Performance Max feed‑only vs classic Google Shopping

What is PMax feed‑only? It’s a Performance Max campaign where you intentionally provide only your product feed (no extra images, headlines or videos). That nudges Google to allocate budget through the Shopping channel in PMax.

Why choose PMax feed‑only:

• PMax is Google’s focus and receives ongoing product development and AI upgrades.
• PMax now supports many Shopping‑like controls (product exclusions, brand exclusions, product selection).
• PMax supports more bidding strategies than standard Shopping campaigns.
• Using feed‑only future‑proofs your account — standard Shopping may be deprecated over time.

When you might still use classic Shopping

Some agencies revert to standard Shopping for granular control, but that comes with fewer bidding options and may become obsolete as Google pushes PMax. If you want to control brand safety, creative messaging, and specific top‑of‑funnel channels, combine dedicated brand / awareness campaigns with PMax feed‑only for transactional demand.

3. Feed‑only vs full‑asset PMax: brands and long term value

Full‑asset PMax = you supply images, videos, headlines, descriptions and let Google distribute the creative across channels (YouTube, Display, Search, Shopping, Gmail). Google’s promise: touch cold audiences with upper‑funnel creatives and guide them to conversion.

The reality in 2025:

• Most PMax conversions still come from Shopping behavior.
• You have limited control over messages and audience routing in PMax today.
• If your goal is brand building or multi‑stage funnel work, run dedicated campaigns for each objective (e.g., YouTube for awareness, Display for consideration) and keep PMax feed‑only for Shopping conversions.

4. Asset groups inside PMax — should you split product groups?

In PMax you can create multiple asset groups (each with its own creatives and product group). If you are running feed‑only PMax, splitting asset groups usually brings little benefit because the campaign behaves like Shopping.

Do create separate asset groups only when:

• You want to run an A/B test: feed‑only asset group versus full‑asset asset group to compare performance.
• You need to isolate a small product set for reporting or experimental purposes.

5. Audience signals — should you upload customer lists at launch?

Yes. Audience signals in PMax help the algorithm learn faster. If you have a customer list (buyers, high‑value customers, visitors of specific competitor pages), provide it as a signal when launching PMax. Doing so nudges the model towards more relevant audiences quickly and improves early performance.

6. Tracking vs ROAS target — don’t confuse them

These are two separate things:

• Tracking (conversion tracking) reports events and conversion values back to Google — e.g., purchase of €100. Good tracking enables accurate measurement and smarter bidding.
• ROAS target is a bidding strategy you set for the campaign (for example target ROAS of 500% = 5:1). It tells Google what economic outcome you want the algorithm to aim for.

Improved tracking does not eliminate the need for a ROAS target if that target reflects your business constraints. Always ensure you have accurate tracking and choose the bidding strategy that matches your goals.

7. Using AI / ChatGPT to write product titles and descriptions

Short answer: use it. Pierre‑Baptiste’s agency uses proprietary AI to optimize feed titles and descriptions, and Google does not penalize feed text generated with AI — especially when it improves performance. The priority for Shopping remains feed quality: titles, descriptions, images, and competitive pricing.

Remember: feed quality accounts for ~90% of Shopping performance. Invest in clean, relevant, keyword‑rich product titles and images — whether you create them manually or with AI.

8. Cross‑sell tracking: what you can and cannot know

You can set up cross‑sell tracking in Google Ads to measure whether a product click generated:

1. Only the clicked product (no cross‑sell).
2. The clicked product plus additional items (cross‑sell occurred).
3. Only other products (rare cases depending on attribution).

What you cannot reliably know from Google Ads alone: which exact additional products were bought in a multi‑product order. The tracking will tell you whether the original advertised product converted, and whether cross‑sell volume exists, but not the SKU composition of the cross‑sell basket. For detailed SKU‑level cross‑sell analysis, combine Ads data with your back‑end order data or analytics platform.

9. New: Performance by Channel in Performance Max

Good news — Google has rolled out a channel performance view inside PMax that shows budget/traffic distribution across channels (Shopping, YouTube, Display, Gmail, Search). This feature has appeared in many accounts as a beta and gives much‑needed transparency.

What you can do with it:

• See where spend is going and which channels drive conversions.
• Identify if Google is over‑allocating budget to a poorly performing channel.
• Decide whether you need separate campaigns for channels you want to control.

Note: you cannot yet set exact budget percentages per channel inside PMax — the feature is reporting only. Using feed‑only remains the best way to emphasize Shopping spend from PMax.

Practical checklist to act on today

• If you run an e‑commerce site: prioritize Shopping / PMax feed‑only and maintain an ultra‑clean feed (title, image, price).
• If you need leads: start with Search campaigns to control intent and landing pages.
• Upload customer lists and audience signals at campaign launch to reduce learning time.
• Keep tracking accurate — it feeds the algorithm and reporting. Then set a ROAS target that matches your business goals.
• Use AI to improve feed texts if it increases CTR/conversions — Google has no incentive to penalize useful improvements.
• Monitor the new Performance by Channel report to check where your PMax budgets go.

Conclusion

Performance Max is the direction Google is pushing advertisers, especially for shopping‑centric e‑commerce accounts. For now, the best approach is pragmatic: use PMax feed‑only for transactional Shopping performance, run dedicated campaigns for each funnel stage when you need messaging or audience control, upload audience signals early, and keep tracking and feed quality top notch.

If you manage significant monthly spend and want an external audit or strategy review (Pierre‑Baptiste mentions offering audits for accounts spending >€10k/month), consider seeking expert help — particularly if performance has plateaued.

 

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FAQ

Q: Should I always use Performance Max for e‑commerce?

A: Not always. PMax is generally the best long‑term play for product sales, especially feed‑only for Shopping. But if you need to control top‑of‑funnel creatives or run brand campaigns, create dedicated YouTube / Display / Search campaigns alongside PMax.

Q: Can I remove target ROAS once I have perfect tracking?

A: No. Tracking and target ROAS are different. Tracking provides data; target ROAS is your bidding objective. You need both: accurate tracking and the right bidding strategy aligned with your business targets.

Q: Does Google penalize AI‑generated product descriptions?

A: According to real‑world experience shared in the video, Google does not penalize AI‑generated titles/descriptions when they improve performance. Focus on quality and relevance.

Q: Can Google Ads tell me exactly which products were cross‑sold after a click?

A: Not precisely. Ads can indicate that the advertised product converted or that cross‑sells happened, but it cannot reliably list the SKUs bought as additional items. Use your order data for SKU‑level analysis.

Q: How do I influence where PMax spends my budget (e.g., more Shopping)?

A: The best lever today is the feed‑only approach to bias PMax toward Shopping. Monitor the Performance by Channel report to confirm distribution. True budget allocation controls per channel are not available yet.

Credits

This article summarizes and expands on the video "Google Ads : Je réponds (enfin) à vos questions les plus techniques." by Pierre‑Baptiste (Céos). The content reflects practical recommendations and examples discussed in the video.