I'll certainly trust the Epoch ECI result more when it's out, though it won't be directly comparable to Mythos Preview since Epoch did not have access to Project Glasswing. But I think AECI seems trustworthy. For example from Fable 5 to Sonnet 5.5, AECI went up ~4 points while EECI went up ~3.
cited on: claude-sonnet-5-5
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