Design a messaging experimentation plan for [Offering] across [Region] with clear governance. Deliverables: (1) KPI tree linking messaging to [PrimaryKPI] (pipeline, bookings) and downstream metrics (OTIF, churn); (2) Test matrix across channels (search, paid social, partner co-marketing, events) with hypotheses tied to pain-language vs outcome-language; (3) Sample size calculator inputs and success thresholds; (4) Message variants (H1, subhead, CTA) with character counts; (5) Reporting specification (segment cuts, holdouts, lift vs baseline). Output format: One KPI tree diagram (outline form), a Markdown table for tests (Channel | Hypothesis | Variant A/B | Metric | Min Detectable Effect | Owner), and a weekly executive dashboard template. Include risk guardrails (claims, pricing) and a decision rubric to scale winners across [Timeframe]. Provide guidance for handoff to [RoleOwner] for deployment in [MarTechStack].[/Notes]Upload historical campaign data, approval workflows, and any legal constraints. If possible, share existing naming conventions and UTM taxonomy to align reporting.[/Notes]