Opus 5.5 writes shorter sentences and 95% fewer em dashes, but hedges rise 97%
arena · x · 2026-09-26
Text Arena compared how Opus 5.5 writes versus Opus 5 across high-reasoning Text Arena outputs, finding 10 of 12 writing measures improved:
- Long content words fell from 41.7% to 38.6%, the lowest of any Claude model analyzed
- Sentences are 17% shorter on average (12.14 → 10.03 words)
- Classic AI tells dropped sharply: 95% fewer em dashes and 73% fewer semicolons
- The tradeoff is length: average answers grew 6% (453 → 481 words), the longest in the Opus family
- A new tell may be emerging: hedges like "perhaps" and "arguably" rose 97% (0.39 → 0.77 per 1,000 words), the highest rate of any Claude model analyzed
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