Herm journal

Field notes on getting measured.

Working guides for growth, measurement and AI commerce teams. Every claim numbered, every source classified, every method stated before the number.

15 categories · 107 articles

Latest AI & Technology

The GEO Cat-and-Mouse Game Has Already Begun

Reddit citations in ChatGPT Search collapsed and fan-out queries tripled. What the data shows, what it does not, and why creating information beats chasing patterns.

19 Aug 2026

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The GEO Cat-and-Mouse Game Has Already Begun

Latest articles

Newest first

Acquisition CAC Optimisation: The Four Frameworks That Fix Broken Metrics Learn when to use working, fully loaded, incremental and attributed CAC, how calculation choices change the result, and which metric fits each decision. 15 Jan 2026 · updated 27 Jul 2026 Acquisition The CAC-LTV Squeeze: Why Profitable Growth Matters in 2026 What changed in 2025 and 2026, why weak payback and customer quality are under scrutiny, and what the CAC-LTV squeeze means for growth leaders. 2 Jan 2026 · updated 27 Jul 2026 Marketing Strategies Martech Stack Audit: Capabilities, Cost and Rationalisation Audit marketing technology by capability, usage, dependencies, fully loaded cost and risk to decide what to retain, remediate, replace or retire. 6 Nov 2025 · updated 29 Jul 2026

Data-Driven Marketing

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How to Build a Marketing Incrementality Testing Programme Measure incremental marketing effects using customer holdouts, channel tests, geo experiments and lift studies, then connect results to budget decisions. 2 Oct 2025 · updated 29 Jul 2026

02 Customer Data Platforms: Architecture, Implementation and ROI 03 Zero-Party Data: Collection, Validation and Responsible Use 04 CRM-Driven Marketing: Data, Workflow and Personalisation 05 First-Party Data Strategy: Collection, Activation and Measurement

Personalization and Customer Experience

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Dynamic Creative Optimisation: 3x ROI vs the 67% Failure Trap Dynamic creative optimisation delivers 3x ROI when done right — yet 67% of personalised experiences fail. Here's what separates winners from losers. 21 Oct 2025 · updated 27 Apr 2026

02 The Personalisation Revenue Gap: Why Brands Lose 40%+ 03 Brand Voice Consistency in Personalised Marketing 04 E-Commerce vs Retail Personalisation for Marketers 05 Content Personalisation for Cross-Device Journeys: A UK Guide

Consumer Privacy and Data Ethics

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GDPR & CCPA Compliance: Privacy-First Marketing Build privacy-compliant marketing systems with comprehensive frameworks for GDPR and CCPA. Learn from €1.2B+ in fines, reduce breach costs 39%, and protect customer trus… 30 Sept 2025 · updated 23 Feb 2026

02 Privacy-Personalisation Paradox: Building Data Trust 03 Privacy-Enhancing Technologies for Personalisation 04 Green AI: The Environmental Cost of Personalization 05 Secure Personalisation Under GDPR: A Framework

Customer Acquisition and Retention

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CAC Optimisation: The Four Frameworks That Fix Broken Metrics Learn when to use working, fully loaded, incremental and attributed CAC, how calculation choices change the result, and which metric fits each decision. 15 Jan 2026 · updated 27 Jul 2026

02 The CAC-LTV Squeeze: Why Profitable Growth Matters in 2026 03 Origins of Affiliate Marketing: Pay-for-Performance 04 How to Acquire High-Value Customers: A Practical Framework 05 Customer Acquisition Strategy: Channels, Data and Execution

AI and Technology in Marketing

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The GEO Cat-and-Mouse Game Has Already Begun Reddit citations in ChatGPT Search collapsed and fan-out queries tripled. What the data shows, what it does not, and why creating information beats chasing patterns. 19 Aug 2026

02 AI Content Generation: When Brand Voice Breaks at Scale 03 Conversational AI in Marketing: Commerce, Leads and Measurement 04 Conversational AI in Customer Service: Design and Measurement 05 Marketing Automation Migration: Planning, Testing and Cutover

Marketing Strategies and Optimization

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How to Audit and Rationalise a Martech Stack Audit marketing technology by capability, usage, dependencies, fully loaded cost and risk to decide what to retain, remediate, replace or retire. 6 Nov 2025 · updated 29 Jul 2026

02 Connected TV Advertising: What Separates Results from Wasted Budgets 03 Personalisation Strategies for E-commerce Websites 04 Personalisation Best Practices for SaaS Companies 05 Marketing Optimisation: Operating Model and Decision Framework

Brand Loyalty and Customer Engagement

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How Personalisation Affects Customer Lifetime Value Learn how personalisation can affect contribution, purchase frequency and retention, and how to test whether it creates incremental CLV. 10 Jun 2025 · updated 27 Jul 2026

02 How to Personalise a Customer Loyalty Programme 03 8 Personalisation Examples That Can Support Customer Loyalty 04 Local Business Personalisation for Customer Loyalty 05 Building Brand Loyalty in the Age of Choice

Ethical Marketing Practices

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AI Ethics in Marketing: A Governance and Risk Framework Govern AI in marketing with practical controls for bias, transparency, human oversight, generative content, vendors, monitoring and customer harm. 2 Mar 2025 · updated 28 Jul 2026

02 Ethical Rules for Digital Marketing: A Campaign Checklist 03 The 4Ps of Ethics in Marketing: Product, Price, Place and Promotion 04 Ethical Marketing: Principles, Trade-Offs and Governance 05 Ethical Use of Consumer Data in Marketing

Open Banking and Financial Data in Marketing

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Open Banking Trends Marketers Should Watch in 2026 Track current UK and European open-banking, open-finance, payment and regulatory developments, and what they may mean for marketers in 2026. 4 Mar 2025 · updated 28 Jul 2026

02 Open Banking Customer Engagement: Adoption, Consent and Trust 03 Open Banking Consumer Insights: Methods and Limitations 04 How to Implement Open Banking Data in Marketing 05 Open Banking for Marketers: Opportunities, Uses and Limits

Measuring Marketing Performance

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Personalisation KPIs: Metrics, Formulas and Definitions Learn how to calculate and interpret 19 personalisation KPIs, from recommendation CTR and conversion lift to CLV, opt-outs and decision latency. 3 Jun 2025 · updated 27 Jul 2026

02 Marketing Metrics by Funnel Stage: Formulas & KPIs 03 How to Measure Personalisation Effectiveness and ROI 04 How to Measure Marketing Performance: A Practical Framework

E-Commerce Trends and Competition

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Social Commerce 2026: Turning the Scroll into Checkout Social commerce is set to top $100 billion in 2026. See the platforms, creator tactics, and measurement frameworks that turn browsers into buyers. 16 Oct 2025 · updated 27 Apr 2026

02 Social Commerce in 2025: Turn Scrollers Into Shoppers 03 E-Commerce Trends: Navigating Online Retail in 2025

Consumer Insights and Behavior

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Open Banking Personalisation: Decisions, Use Cases and Guardrails Responsible ways to use open-banking data for personalisation, with practical safeguards for privacy, vulnerability, fairness and customer control. 7 Mar 2025 · updated 28 Jul 2026

02 Competitive Advantage through Consumer Insights

Multi-Channel and Omnichannel Marketing

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Multi-Channel Engagement for Personalisation Discover multi-channel engagement strategies that create personalised experiences and boost conversion rates. Practical implementation tools and real case studies. 29 May 2025 · updated 23 Feb 2026

02 Multichannel vs Omnichannel Marketing: Differences and Strategy

Collaboration and Partnerships in Marketing

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Collaborative Marketing: Partnering for Greater Reach Expand reach with strategic partnerships. Co‑branding plays, cost sharing, and partner selection tips. 4 Feb 2025 · updated 8 Aug 2025

Recently published

Newest first

01 The GEO Cat-and-Mouse Game Has Already Begun AI & Technology 02 CAC Optimisation: The Four Frameworks That Fix Broken Metrics Acquisition 03 The CAC-LTV Squeeze: Why Profitable Growth Matters in 2026 Acquisition 04 Martech Stack Audit: Capabilities, Cost and Rationalisation Marketing Strategies 05 Connected TV Advertising: What Separates Results from Wasted Budgets Marketing Strategies 06 AI Content Generation: When Brand Voice Breaks at Scale AI & Technology 07 Conversational AI in Marketing: Commerce, Leads and Measurement AI & Technology 08 Dynamic Creative Optimisation: 3x ROI vs the 67% Failure Trap Personalization

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AI and Technology in Marketing 7 articles 7 Brand Loyalty and Customer Engagement 5 articles 5 Collaboration and Partnerships in Marketing 1 article 1 Consumer Insights and Behavior 2 articles 2 Consumer Privacy and Data Ethics 8 articles 8 Customer Acquisition and Retention 8 articles 8 Data-Driven Marketing 27 articles 27 E-Commerce Trends and Competition 3 articles 3 Emerging Technologies in Marketing 0 articles 0 Ethical Marketing Practices 5 articles 5 Marketing Strategies and Optimization 6 articles 6 Measuring Marketing Performance 4 articles 4 Multi-Channel and Omnichannel Marketing 2 articles 2 Open Banking and Financial Data in Marketing 5 articles 5 Personalization and Customer Experience 24 articles 24

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