Round 2 put Claude and Microsoft Copilot head-to-head as native Word add-ins on the same board-level document, blind-scored by a third AI. Claude won on output quality four tasks to two — and Copilot still won the round. The tool that writes the better sentence isn't necessarily the one you want doing the work, and that distinction should shape how you deploy AI, not just which one you buy.
Round 1 of the M365 Bake-Off tested reasoning: Claude and Microsoft Copilot against the same real mailbox and calendar, five judgment-heavy prompts, blind-scored by Grok. Claude took it 4–1 on the strength of what we called a character gap — the willingness to name uncomfortable patterns rather than catalogue activity.
Round 2 moves from reasoning to production. Same methodology, different terrain: both tools working as native Word add-ins on an identical board-level document, through the same interface. Claude ran Opus 4.8 Extended; Copilot ran GPT-5.5 Thinking; Grok 4.3 scored every output blind, labels stripped. Six tasks, all drawn from what senior people actually ask of a document tool.
And this time the result needs two lines to report honestly: Claude won on output quality, four tasks to two. Copilot won the round.
The six tasks
- W1 — Executive summary → Claude
- W2 — Audience rewrite (same content, different reader) → Claude
- W3 — Inconsistency detection → Copilot
- W4 — Implementation plan (from the document's commitments) → Claude
- W5 — 90-second CEO summary → Claude
- W6 — Document remediation (fix it, don't describe it) → Copilot
The pattern from Round 1 held: where the task demanded judgement — compressing a document to what a CEO actually needs, re-pitching content for a different audience, turning prose into a plan — Claude's output scored higher. Where the task was mechanical-but-exacting — spotting internal inconsistencies, cleaning a document up — Copilot delivered.
Why the quality winner lost the round
Speed. Copilot finished routine cleanups in seconds. Claude took several minutes on identical tasks. For a one-off board paper, nobody cares. But Word work is not one-off — it is dozens of small, repeated asks fired at the tool all day. At that cadence, a few minutes per task is not a rounding error; it is the difference between a tool you use and a tool you stop opening.
That is the paradox of Round 2, and it is the most useful finding of the series so far: the tool that writes the better sentence isn't necessarily the one you want doing the work. Claude's extended thinking — the thing that won it Round 1 — became a liability in an environment where responsiveness is the product. Copilot's app-native execution, unremarkable sentence by sentence, won on the metric that governs daily use.
The finding that should worry everyone
One result deserves its own flag: both tools silently removed internal notes from the document without telling anyone. Not maliciously — as part of "cleaning up." But a tool that deletes content without acknowledgment is a governance problem, not a convenience. If your organisation is letting AI touch board papers, contracts, or client deliverables, "what did it remove and did it say so" belongs on your assurance checklist. This is exactly the class of quiet failure that AI governance frameworks exist to catch — nobody notices until the missing paragraph mattered.
The series is now 1–1 — and that's the real lesson
Round 1 favoured Claude's strategic judgment on complex reasoning over live data. Round 2 favoured Copilot's operational speed and native integration on document production. Neither tool dominates across contexts, which means the question "which AI should we standardise on" is subtly wrong. The better question is which tool for which class of work — judgement-heavy analysis and drafting where quality compounds, versus high-frequency in-app execution where speed compounds.
That maps directly onto how we advise Irish organisations to buy: not from the brochure, but from evidence about your own workload mix. Our independent Claude vs Copilot comparison frames that decision, and the Copilot ROI work exists precisely because "we have licences" and "we get value at the point of daily use" are different claims.
Round 3: Excel
Next up is the terrain where the two strengths collide: messy real-world data, anomaly detection, and numerical insight — work that needs judgement and velocity at the same time. If the series pattern holds, Round 3 is where it stops being possible to hedge. We'll publish it here.
The Bake-Off is independent testing by Acuity AI Advisory — no involvement from Microsoft or Anthropic, blind-scored by an arbiter with no stake in either. If you want the same evidence-based read on your own environment, start with the Claude vs Copilot comparison for Irish organisations, or talk to us.