DeepSeek's cheap model just beat its own flagship, so DeepSeek killed the flagship. Since September 14, every API call to V4 Pro gets answered by V4.1 Flash instead, at Flash prices, because Flash scores 74.2 on the DeepSWE coding benchmark against the flagship's 62.7. Flash costs 15 cents per million input tokens and 60 cents per million output off-peak. GPT-6 Astra and Claude Fable 5.1 both charge $10 and $50. On output that's a 40 to 80x gap depending on the hour, and for coding agents it…