The JAMA Network Open study's headline figure is specific in a way that most coverage has not preserved. The 80%-plus failure rate applies to differential diagnosis under incomplete data — the partial-information scenario that defines early clinical presentation. The same models that fail there produce final-diagnosis accuracy above 90% when given complete clinical information. That gap is not a flaw to be patched; it reflects a structural mismatch between how these models were evaluated and how they are being asked to perform. Benchmarks reward models for processing structured inputs correctly.…