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Both eta ceilings in sec 6.6 come from adversaries optimising something else (revenue, reorg depth), so they bound eta from above without bounding the damage from below. Optimising the estimate directly needs no ratio transform: each transition consumes exactly one block-finding event, so minimising D-hat = (canonical + p_ref * countable uncles)/events is a plain average-reward MDP over the transition table that already carries the orphan counts. One value-iteration pass, no bisection. Unconstrained, the answer degenerates -- and usefully. The optimum is pure abstention: publish nothing, adopt when overtaken, D-hat = 1 - alpha exactly, revenue zero. That is sec 6.4's withholding, which the report already shows is CORRECT measurement rather than mis-measurement, so the unconstrained objective asks the wrong question. The constrained one bites. Sweeping lam * (adversary blocks) - (contribution to D-hat) enumerates policies; the line of interest is where revenue SHARE reaches alpha, i.e. where attacking costs nothing versus mining honestly. At alpha=0.4 such a policy drives D-hat to 0.642 where the revenue-maximiser reaches 0.811 -- 17 points of extra deflation bought with the selfish premium alone. At 0.36 and 0.45 the gaps are 0.082 and 0.103. Below the 1/3 threshold nothing profitable deflates, so the exposure starts exactly where selfish mining does. This revises two claims that were about revenue but read as though they were about the adversary in general: sec 6.7's "the adversary frontier is exactly optimal selfish mining; no compounding lever remains" and sec 8.2's echo of it. Both now say the PROFIT frontier is bounded and the estimator frontier is not the same policy. Note the sweep parameter is deliberately non-monotone in revenue -- selfish mining takes a bigger share of a smaller pie, so raw block rate is maximised by honesty and large lam returns there; it enumerates policies rather than tracing a path. Also closes a fairness loop these findings opened. Sec 6.7(1) credits uncle rewards with compensating orphaned honest producers, computed on the SM1 race where every orphan is a first-fork block. Under a private chain 20-40% of the honest blocks destroyed are unreferenceable by construction, so those producers are uncompensatable at ANY w_u -- not underpaid because p_ref is low, but unreachable because no valid block may name them. The fairness guarantee inherits the same first-fork ceiling as the density repair. Logged as item 19, flagged as a protocol-design question rather than something a schedule fixes. _solve_mdp is refactored into _solve_reward/_greedy_policy/_stationary/ _policy_rates so both objectives share one implementation; optimal_policy_stats reproduces its committed figures exactly (eta 0.4413, D-hat 0.9447/0.8111 at alpha=0.4). 251 tests pass. Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>