Graphite: Opus 5.5 says 'this matters' 116x more often than humans

Marketing firm Graphite compared 10,000 pre-ChatGPT articles with AI rewrites and found 13,000 phrases at least twice as common in AI prose. Claude Opus 5.5's top tell is 'dependable' (23x more frequent), while OpenAI's Astra favors 'not simply X' and 'rather than relying on X' (over 100x more frequent). Em-dash use has dropped sharply, but the overall number of tells is holding steady.

• Graphite found 13,000 phrases at least twice as common in AI text as in human writing
• Opus 5.5 uses 'this matters' 116 times more often than human samples
• Astra uses 'not simply X' and 'rather than relying on X' over 100 times more often
• Opus 5.5 uses em-dashes 99% less often than Opus 5