From Fragmented Signals to Unified Decisions: Inside eTail Boston’s Attribution Strategy Debate

In performance marketing, attribution is no longer about proving clicks, it’s about defending budgets, finding growth across fragmented touchpoints, and aligning investment to the real levers of profitability.

At eTail™ Boston, a panel featuring Leslie Griffin (Ahold Delhaize), Tiffany Lee (Fleet Feet), Matt Butler (Bonsai), and Dom Devlin (Fospha), moderated by Oliver Mountain (Bidnamic), unpacked what it takes to measure performance in 2025’s multi-channel, privacy-first environment.

The conversation moved beyond theory, grounding the discussion in operational realities, shifting data landscapes, and the new capabilities of measurement platforms.

Dom Devlin opened with a challenge to the room: many marketing organisations remain structurally biased toward bottom-of-funnel channels because that’s where their models can “prove” results.

When attribution is anchored in last-click or click-path logic, budget flows to the closest touchpoints before conversion, starving upper-funnel investment and undercutting long-term demand creation.

Fospha’s analysis shows the difference clearly. Brands allocating 20% or more of budget to upper-funnel activity are achieving nearly double the marketing efficiency ratio (MER) compared to brands spending less than 10%.

This isn’t about sentiment, it’s economics. Without a full-funnel view, businesses over-invest in short-term gains at the expense of sustained revenue growth.

Matt Butler pushed the conversation further: the real problem isn’t only about tracking gaps due to privacy regulations or platform restrictions. The nature of the data that marketers can collect has also changed.

With customer journeys stretching across more platforms, devices, and walled gardens, even seemingly complete click data is a partial picture. “Ease of measurement” is still driving budget allocation, a dangerous bias when the channels that are hardest to measure often play the most significant role in influencing purchase intent.

From a brand-side perspective, Leslie Griffin and Tiffany Lee emphasised a different challenge: securing trust from Finance.

Non-deterministic models like MMM (marketing mix modelling) can feel abstract to financial controllers who prefer direct, short-term ROI attribution. Without alignment early in the process, marketing risks having its budget dictated by the narrowest, most conservative measurement lens.

Fleet Feet’s experience is a case study. When upper-funnel spend was cut for eight months, conversion rates and new customer acquisition suffered. Only when awareness investment was restored did performance recover - proof Tiffany’s team could take back to finance and franchise partners.

For years, MMM has been dismissed as too slow for tactical decision-making - a “strategy deck” tool, not an operational one. Dom countered that narrative, outlining Fospha’s approach to always-on, granular MMM.

By integrating directly with media buying systems, Fospha’s models can feed bidding algorithms daily, giving brands the ability to scale experimental channels with real incremental signals.

This transforms MMM from a quarterly or annual review tool into a dynamic optimisation engine bridging strategic allocation and day-to-day campaign management.

One of the most urgent revelations from the panel came from Dom’s data:
For some brands, up to 42% of Amazon sales are influenced by non-Amazon paid media.

Without the ability to connect cross-channel impact to marketplace performance, those sales get classified as “organic” within Amazon, obscuring the real ROI of external campaigns.

At Amazon’s market share, this misattribution equates to hundreds of billions of dollars in uncredited revenue. The same pattern is emerging in newer retail environments like TikTok Shop and other fast-growing marketplaces.

The panel agreed that the days of measuring each channel in isolation are over. A modern measurement strategy must:

As Leslie noted, sometimes the best move is accepting a lower short-term ROAS in exchange for long-term customer value, especially when spend deepens multi-channel relationships.

Tiffany shared a case study in reframing affiliate marketing. Historically viewed as unprofitable, Fleet Feet reduced its affiliate roster to focus on content-driven partners.

By prioritising affiliates who could deliver genuine product storytelling alongside trackable performance, the channel shifted from a margin drain to a brand-aligned growth lever - blurring the lines between content investment and last-click sales.

Leslie offered a pragmatic approach for balancing optimisation and innovation:

This ensures the testing budget is large enough to generate valid readouts, rather than spreading risk too thin across too many experiments.

Dom closed by positioning measurement not as an after-the-fact report, but as an operating system for growth.

In practice, that means connecting MMM, incrementality testing, and granular attribution into a single decision loop that guides both strategic allocation and daily campaign execution.

It’s also where Fospha’s proposition comes into sharp relief. As a full-funnel, privacy-safe measurement foundation, Fospha unifies performance across all channels, including hard-to-measure marketplaces, and connects spend directly to incremental revenue outcomes.

By reconciling and modelling data daily, Fospha equips marketing teams to:

In Dom’s framing, that’s how you move from “measuring” marketing to actively steering it.

The panel didn’t pretend that attribution will ever be perfect. But the message was clear: the winners in 2025 will be the brands that:

For senior marketers, the challenge is not just building the right model, it’s operationalising it. As Dom Devlin emphasised, Fospha’s measurement foundation enables exactly that: a full-funnel, privacy-safe view that reconciles data daily, attributes hard-to-measure channels like marketplaces, and connects spend directly to incremental growth.

Spots are limited, grab yours now.

Independently Created. Not affiliated with eTail Boston.

Unofficially eTail is a ClickZ Media publication in the Events division