I wish they'd release some data or evaluation methodology alongside such claims. It just seems like empty words otherwise. If they did 'extensive safety testing' and don't release material, I'm gonna say with 90% certainty that they just 'vibe-red-teamed' the LLM.
I really hope they release something as well, because I loved their research papers on analyzing how Claude thinks[0] and how they analyzed it[1] and I'm eager for more.