premise never left the repo
Separate agent, second tier-L review in this project. Six of seven
challenges conceded. The survey's headline finding is WITHDRAWN, not
softened.
C4 kills it, and the reviewer ranked it fourth. A FirstLegal policy --
take legal[0], no heuristic at all -- scores 0% at five and six seats
where GreedyPolicy scores 100%, and 77.5% at two seats where greedy scores
66%. Two unsophisticated agents span the entire range at the same seat
count. "The game is too easy at 5-6 seats" is therefore a statement about
GreedyPolicy, not about GROUND. The rescue the reviewer offered -- greedy
hits the 12-point ceiling in 200/200 deals, so the 6p row is a rules claim
-- dies on the same data: FirstLegal reaches that ceiling never.
C1: the per-node cost was wrong by 30-50x. The timer started before the
seed loop, so "us/node" included two setups, an entire greedy game and a
full validate+fold replay, divided by player-decision count. The tell was
in my own published output and I did not look at it: the figure FELL
(161/139/112) as branching ROSE (4.7/7.4/9.1), which no per-enumeration
cost can do. Re-measured with the clock around legal_commands alone:
3.0/3.5/4.1 us, now rising with branching. The reviewer measured 15.6-20.4
by a different isolation; we disagree by ~5x and neither has established
which is right, so T04 must benchmark it with criterion rather than adopt
either number.
C6: "exhaustive search is out at any seat count" is false -- ~3 seconds
over the last two rounds at 3p. With C1's correction the budget is
~10^5-10^6 nodes and bounded endgame search fits, so ADR-0013 cannot open
with "exhaustive is impossible, therefore determinized sampling" --
especially as sampling carries strategy fusion that exhaustive search does
not.
C3: the finding failed the admissibility rule this project wrote nine
hours earlier. 6/9/12 are sums where GROUND-WP-0004 T02 requires
per-priority rows, and the harness has no assertions, no --self-test and
no make target, so nothing can turn it red -- a `default` artifact wearing
a `counterexample` label, by CB-WP-0022 T05's own distinction.
C2: the ratio story explains nothing; 3p and 4p share deal, threshold and
ratio and differ by 12.5 points of win rate. C5: "explains the
maintainer's report" is contradicted by lib.rs:2487, which records his
losses as 3-player games on the pre-ruling deal, arithmetically unwinnable
at 6 against 7.
T06 exists to report to GROUND-WP-0005, which is BLOCKED waiting on a
difficulty baseline. Had this proceeded they would have been invited to
move thresholds on the strength of one bot's behaviour. That is the fifth
wrong premise this project would have sent them, and the second stopped by
an adversarial review rather than by a control. Both tier-L reviews here
have now caught a false headline that every gate passed.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
CB-RES-0008 with a runnable baseline
(games/ground/examples/difficulty-baseline.rs), and the measurement
produced a finding before any solver exists.
A GREEDY BOT WINS 200 OF 200 GAMES AT FIVE AND SIX SEATS. Median margin
+3, 11.8-12.0 points available against a threshold of 9. The curve is
66% / 82.5% / 95% / 100% / 100% across 2/3/4/5/6 seats.
Row-level, as GROUND-WP-0004 T02 requires: available points 6 / 9 / 12
against thresholds 5 / 7 / 9, so the ratio RISES with seat count (1.20,
1.29, 1.33) while the table also gains actions per round to clear it with.
Three multipliers pointing the same direction.
It also explains the maintainer's report without needing a solver at all:
"I felt it was too easy but then we lost" is two true statements about
different seat counts.
Cost measured and it rules out the obvious approach. Branching is small
(mean 4.7-9.1) but legal_commands costs 112-161 us per call because it
filters candidates through full validate. Exhaustive search is out at
every seat count; 10^4-10^5 nodes is 1.4-14 seconds, which is the budget
the ADR must design inside.
Prior art names the trap: determinized search (PIMC) suffers strategy
fusion (Frank, Basin & Matsubara 1998) -- the search picks different
actions in states a real player cannot distinguish, so the witness may
require knowing what was on top of the deck. Such a line still replays
green, so the checkability benchmark does not catch it. Honesty and
checkability are different properties; stated explicitly so T03 cannot
conflate them.
The survey states its own most likely killer up front (§6): a view-only
search cannot fold events, so making the information boundary structural
rather than a promise may not be affordable. Better found here than in
T05.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>