In short
The argument would be shown wrong if grammar coverage stalls, if more than 10% of validator-passing documents turn out semantically wrong in production, or if the case corpus proves impractical to build.
In the video · scene 17
- Grammar coverage stalls. If most screens or configurations in a real product cannot be expressed without per-case grammar extensions, the fixed cost never amortises and the horizontal route was correct.
- Semantic error survives validation. More than 10% of validator-passing documents turn out semantically wrong in production, and review load stays proportional to output volume.
- The case corpus proves impractical to build, leaving verification dependent on reading. This is the failure mode with the strongest historical precedent.