Context
The original route hoped that paired-digit reverse-and-add histories would reveal a forced substitution hierarchy analogous to an aperiodic monotile construction.
Proof or evidence
The pinned replay attains all 10^k digit blocks through k=4 and all 2^k carry-in blocks through k=12. That finite observation is sufficient to reject this particular hoped-for low-complexity signature at those scales, but not richer conditioned presentations.
Verification notes
The public record adopts the source correction: this is a stopped route, not a theorem that no substitution, tiling, or finite-state method can work.
Limitations
- The evidence is bounded and representation-specific.