According to Anthropic, participants who used AI tools completed their tasks about two minutes faster on average, but their quiz scores were significantly lower by 17%, equating to a drop of roughly two letter grades. As reported by Anthropic on Twitter, this finding highlights a critical consideration for businesses and educators evaluating the efficiency versus effectiveness of AI-assisted work. The results suggest that while AI can speed up task completion, it may negatively impact knowledge retention and accuracy, offering important insights for companies integrating AI into assessment or training environments.