The tutorials flooding YouTube on April 13 share a structural omission: the distance between a working demo and a capital-safe deployment. A Claude-powered arbitrage bot that executes correctly in a sandbox can still blow an account in live conditions without position-sizing rules, latency controls, or a backtesting layer that validates signals historically. The — vectorbt for backtesting, Kelly Criterion for sizing, CCXT for execution — is the part the tutorial format is structurally unable to convey in a short video. That omission is…