Claude Opus 5.5 uses 95% fewer em dashes, but its answers are getting longer

Anthropic's Claude Opus 5.5 model has changed its writing style to look less like AI-generated text, using 95% fewer em dashes (dropping from 15.2 to 0.8 per 1,000 words) and shorter sentences compared to its predecessor Opus 5. While the new model produces more natural-sounding writing with simpler wording and fewer obvious AI patterns, it compensates by generating longer overall responses, averaging 481 words instead of 453.